The Legend of Zelda: Tears of the Kingdom has an incredibly large amount of items, weapons, and armors for you to make use of. Thanks to the game's fusion system, all of these can wildly affect your aesthetics. Such as having a large rock fused to your sword, turning it into a makeshift stone mallet.
You could bedazzle your shield with various gemstones. However, one feature you should definitely be making use of is dying your armor to keep your garb looking fresh if you are wearing the same one for most of the game.
Where Can You Dye Your Armor?
You can get your armor dyed over at the Kochi Dye Shop. You will be able to find this shop in Hateno Village. Inside of it will be an NPC named Sayge. There are lots of armor that you will not be able to dye. This can include ones with a prefix describing how they have been worn down or are old. Armors from Amiibo figures are another such example.
Sayge also runs a paraglider customization service that allows you to customize your paraglider look as well.
How Do You Dye Your Armour?
It will cost you a fee of 20 rupees, but that is not all it will cost you. You will need to provide the items you wish to be used to dye your armor. You will need to provide 5 items that bare the same color as the dye you want. This will give you a preview of what the armor will look like after it has been dyed. Clicking confirm will then cue a short cutscene and dye your armor that color.
Item Color Requirements
Items are pretty colorful in the game. If you like your gear blue, be sure to hang onto as many blue items as you can find. Some examples are Blue Nightshade and Winterwing Butterflies. Apples are an easy choice for red as you can get a lot of them at once (golden apples don't count). It is recommended you don’t use gems and combat items as you may regret running short on them later.