The Wall Jump mod adds a double jump to Minecraft to aid in hopping a few blocks higher than normal height. By hitting ‘J’ you’ll open up the settings for the mod and you can customize a few aspects to suit your needs. The big option there being the ‘auto-turn’ function. This will determine if you do a 180 degree turn after your jump or if you simply jump a bit extra off the wall.
At some point in the game you may come across an area that you’d prefer to get to by jumping, whether it be by design or otherwise. You could even create a structure that’s only accessible by this method!
The double jump is easily achieved by running up to any wall, jumping, and then hitting the jump key again. If you have auto-turn on then you’ll quickly turn around to possibly jump up the next wall across from you. This makes it easier to scale adjacent walls in no time.