PacksHQ makes one of the BEST texture packs for hypixel skyblock. They have a huge team run by ImperiaL that makes Skyblock Pack, which is one of the most popular packs in the game. It is super easy to install using one of two methods: SkyClient and Manually.
Install PacksHQ Using SkyClient
SkyClient is an incredibly easy way to install mods and texture packs, but it does limit you to one specific client. If you are interested in using it, I would first suggest you install SkyClient using this link. Once you have, come back to this page and I will show you how to add the pack to your SkyClient instance.
PacksHQ is available in SkyClient as you can see in the image above. It is located in the bottom right on my screen, but may be somewhere else on yours. There are a few options, 16x and 32x, which correspond to higher resolutions. 32x is higher quality, and will also require more computer and power usage.
Install PacksHQ Manually
To install PacksHQ’s Skyblock Pack you will need to first download the pack. You will need to visit https://packshq.com/content/packs/index.html and choose the appropriate pack. On this pack there are two options, Normal and Dark UI overlay. Dark UI simply changes the UI to be in a dark-mode state, which some people enjoy. It is completely up to you and the installation tutorial remains the same. (NOTE: For some versions of the pack you will need to install Optifine)
Once it is downloaded, you will need to place it in the correct folder. Open your downloads folder, and find the file. Drag that window to one side of your screen. Next press the Windows Key + R. Type %appdata%\.minecraft/texturepacks. Then simply drag the file into that folder. Congratulations, Packs HQ’s Skyblock Pack should now be installed into your Minecraft installation!