- Download the file in this repository entitled either "legacy" or a string of letters and numbers.
- When downloaded, navigate to where the file is located (most likely, you downloaded it into Downloads)
- Right click resource pack file, and click Rename.
- (When doing this step, make sure to rename the whole name, including the current extension) Rename it to legacy.zip
- Then press enter.
- Then double click legacy.zip (and out pops a folder with all of the resourcepack data).
- Move the legacy folder into the resourcepacks folder in your minecraft folder.
- You should be able to download the repository entitled "legacy" and be able to just throw it into your resourcepack folder, which is in your minecraft folder.