1- Hold crouch
2- Let go of crouch
3- At the same time you let go of crouch, guardian angel (if done correctly, you should GA on an upwards angle)
Consider the solution to be:
If you’re still stuck after attempting the possible solutions above, consider finding the map guide video in the Mercy Parkour Code Spreadsheet (Mercy Parkour Codes) to see the intended solution or join the Mercy Parkour Discord (Mercy Parkour Server) to ask for help.