Start by hitting the big blue download button. Then, simply drop the downloaded zip file in the "datapacks" folder of your world save (<world>/datapacks).
Open your world and do:
/reload

IMPORTANT: If you ever add or re-enable other data packs in your world afterwards, do:
1. /datapack disable "file/Synchronized Advancements.zip"
2. /datapack enable "file/Synchronized Advancements.zip" last
These commands are required to make the data pack sit on top and overwrite other advancements.

ALSO IMPORTANT: Only advancements that haven't been completed before they were added to the data pack will be tracked after the generated data pack is enabled.
To manually trigger an advancement for all, follow these steps:
1. /advancement revoke @s (from|only|through|until) <advancement>
2. Repeat the same command, but now replace 'revoke' with 'grant'

Download the generator software I wrote here and follow the instructions that appear on screen.

I test all my creations, but bugs happen no matter how long you test something. Whenever someone experiences a bug, I do my best to fix the issue. You can help me by providing any useful information. You can never give me enough information, but please send it in a DM instead of placing it in the comments. You can still place a one-liner in the comments stating the issue to make the community aware, but that alone isn't enough to help me fix the issue.

• Checklist: Are you using the right version? Did you do /reload after dropping the datapack in? After /reload, does the datapack show up green in /datapack list?
  
• What is the issue? Does the datapack not seem to be working at all or is there a specific feature you are having issues with?
  
• What happened? Please give me all the steps needed to reproduce the issue. The faster I can experience it, the faster I can solve it.
  
• What did you expect to happen instead? This helps me understand your point of view and determine if the issue described is actually the issue I need to fix. The bug you are experiencing could just be a side effect of something else that doesn't behave as expected.