Cizlin
Customization Part 1 - Technical Preview July 2021
Updated: Aug 17, 2021
The July 2021 Technical Preview gave us our first hands-on look at the customization hierarchy and offered a subset of options to change to our liking. There was a lot shown in this build, and this will be an extremely lengthy article as a result. Prepare for a ton of screenshots!
Note that the Sources and other information associated with each item are subject to change and may be very different when the game launches this Holiday.

The Customization menu could be accessed from the Main Menu by switching to the Customization tab. From there, players could choose to access one of the following four options:
Armor Hall - Armor customization
Weapons Bench - Weapon customization
Vehicle Bay - Vehicle customization
Body & AI - Body type, Prosthesis, and Person AI customization
There was a fifth option that was made inaccessible in-game: Presentation. Even so, the Halo Waypoint mobile app allowed players to access this section and choose their own Player Emblem.
Due to the length of this article, the Body & AI and Presentation customization sections can be found in the Customization Part 2 - Technical Preview July 2021 article.
Armor Hall
The Armor Hall is the designated location for all Armor customization. Although more details are provided below on each of the following Armor Core Sockets, this list will allow you to skip to a desired Socket to see all the customization options visible within this Technical Preview. If a Socket is not listed, it did not have any items that could be seen within the Tech Preview.

Name: Mark VII
Quality: Rare
Manufacturer: Materials Group
Released: Season 1
Lore: The latest generation of powered assault armor
Source: Unlocked by default
When you visit the Armor Hall, you must first select an Armor Core to equip or modify. In the Tech Preview, only the Mark VII Armor Core was available, but there will be three at launch. All cosmetic items are tied to a particular core, so everything shown in this section will be exclusive to the Mark VII Armor Core at launch.
All cosmetic items have a Lore page (shown above for the Mark VII Armor Core), where players can view the manufacturer, when the item was released, the in-universe Lore for the item, and either when it was acquired (if unlocked) or how to obtain it (if locked). Players can also Favorite customization items to easily find their preferred options again.

Players can also access the Core options from this menu, which are common between all Armor, Weapon, and Vehicle Cores. The first option is a toggle for Favorite, which can be done outside this menu. The second option, an Equip toggle, can also be done outside the menu.

The third option is rather neat, as it is a new feature for Halo Infinite. If you really like the customization choices you've made, you can choose to Hide UI, temporarily making the UI invisible so only your customizations are shown. Pressing any button will bring the UI back.

The fourth option allows players to randomize their Core. This will select a random owned item for each socket on the Core, useful for changing up your look on the fly without needing to dive into each socket.

The fifth option allows players to Optimize their Core. That is, each socket will automatically equip the highest quality item (on the scale of Common < Rare < Epic < Legendary).

The sixth and final option can be used to restore all sockets within a Core to their defaults.

The Mark VII Armor Core has multiple Sockets, each representing an individually customizable portion of the armor. The first Socket is Armor Kit, which is a group of items that are applied to the armor as a set. Items within an Armor Kit cannot be modified within changing the Armor Kit itself. No Armor Kits were available in the Tech Preview.

The second Socket is the Coating, which includes the paint, materials, and patterns displayed on the armor.

The third Socket is the Helmet, which is fairly self-explanatory. Helmets and corresponding Helmet Attachments are chosen within this Socket.

The fourth Socket is the Visor. Visors can differ in color, pattern, and finish.

The fifth Socket is the Chest. The default Chest is shown here and can be equipped by deselecting the currently applied Chest item.

The sixth Socket is for the Left Shoulder. As with the Chest, None is an option here. The unequipped option is shown above.

The seventh Socket is for the Right Shoulder. The icon shown for this Socket is likely a placeholder implemented during the Tech Preview. As with the Left Shoulder, players can unequip their current Right Shoulder selection to remove the Right Shoulder armor.

The eighth Socket is Gloves, which controls the armor on the backside of the player's hands.

The ninth Socket is for the Wrist. As with the Chest and Shoulders, the Wrist can be unequipped if the player desires, as shown above.

The tenth Socket allows the player to customize their Hip. Like the Armor Kit, Chest, Shoulders, and Wrist, this Socket allows the player to have no Hip item equipped.

The eleventh and final Socket available in-game within the Technical Preview was the Knee Pads. However, there was one more Socket that could be seen through the website.

The twelfth Socket could only be seen on the Halo Waypoint Beta website and app during the Technical Preview. Although no Armor FX were shown, we now know this customization option will be featured in Halo Infinite.

Selecting a Socket will bring up a list of items that can be equipped in that Socket. All customization menus at this level have the same layout, with a Filter & Sort to the upper right of the customization items. Favorited items have a small star in the upper right corner of their tiles.

Players can Filter and Sort by numerous categories. The first is the Ownership category, where players can filter to only see items they own or items they don't yet own.

Players can also choose to filter for only those items they have Favorited, making it very easy to remember and find the items you liked the most in a sea of options.

The third and final Filter option is Quality, allowing the player to show only those items matching a particular quality rating (Common/Gray, Rare/Blue, Epic/Purple, Legendary/Yellow).

Players can also Sort the customization items by several categories. Default puts the currently equipped item at the front of the list. The rest of the items are then sorted in the following order:
1) Ownership status (owned first)
2) Quality (Common to Legendary)
3) Name (A to Z)
Players can also choose to sort first by Quality, Season, Date Acquired, and Name.

Finally, players can choose the Sort Order (Ascending/lowest-to-highest or Descending/highest-to-lowest).
Coating
The Coating socket for the Mark VII Armor Core allows a player to customize the armor's colors, materials, and patterns all in one indivisible package. There were a ton of Armor Coatings unlocked by default, and several more could be earned in the Free track of the Battle Pass or through completing the Capstone Challenge. Only one Armor Coating was in the Paid Battle Pass track, and only one Armor Coating was available for direct purchase through the Shop. Some Armor Coatings could not be obtained through any means, even though they were visible in the Tech Preview.
The below Armor Coatings are shown in alphabetical order, which means that the rarities will be intermixed.

Name: Arctic Void
Quality: Epic
Manufacturer: UNSC
Released: Season 1
Lore: What's cooler than cool?
Source: Unobtainable

Name: Bleached Bone
Quality: Legendary
Manufacturer: UNSC
Released: Season 1
Lore: In the end, the keelbugs conquer all.
Source: Unobtainable

Name: Blue Rampage
Quality: Epic
Manufacturer: UNSC
Released: Season 1
Lore: Don't stop for anything.
Source: Reach level 14 in the Season 1 Battle Pass: For our Tomorrow (Paid).

Name: Cadet Blue
Quality: Common
Manufacturer: UNSC
Released: Season 1
Lore: Custom paint and materials.
Source: Unlocked by default.

Name: Cadet Grey
Quality: Common
Manufacturer: UNSC
Released: Season 1
Lore: Custom paint and materials.
Source: Unlocked by default.

Name: Cadet Red
Quality: Common
Manufacturer: UNSC
Released: Season 1
Lore: Custom paint and materials.
Source: Unlocked by default.

Name: Cloven Seafoam
Quality: Rare
Manufacturer: UNSC
Released: Season 1
Lore: Custom paint and materials.
Source: Reach level 6 in the Season 1 Battle Pass: For our Tomorrow (Free).

Name: Cosmic Corruption
Quality: Epic
Manufacturer: UNSC
Released: Season 1
Lore: Custom paint and materials.
Source: Reach level 16 in the Season 1 Battle Pass: For our Tomorrow (Free).

Name: Estate Gold
Quality: Legendary
Manufacturer: UNSC
Released: Season 1
Lore: Not standard issue.
Source: Unobtainable

Name: Ghost Grey
Quality: Epic
Manufacturer: UNSC
Released: Season 1
Lore: Even the dead can tell tales, with the right equipment.
Source: Reach level 17 in the Season 1 Battle Pass: For our Tomorrow (Free).

Name: Hexen Slate
Quality: Rare
Manufacturer: UNSC
Released: Season 1
Lore: Humanity is ignorant of the miracles and secrets beneath their feet.
Source: Unobtainable.

Name: Karaba Sirocco
Quality: Rare
Manufacturer: UNSC
Released: Season 1
Lore: Don't forget to write.
Source: Reach level 2 in the Season 1 Battle Pass: For our Tomorrow (Free).