Rocksmith 2014 Edition
47 Achievements
1,000
80-100h
Xbox 360
Ready to Session
Complete 4 Session Mode Missions
10
How to unlock the Ready to Session achievement in Rocksmith 2014 Edition - Definitive Guide
When you get a mission to try Session Mode, you'll start getting missions that walk you through a sort of tutorial. Just take each mission as it comes, follow the steps precisely and in order, and you'll end up getting this achievement before you've even tried all the Session Mode features.
Missions will come up that require you to go to session mode. Once you've done your 4th one of those. you'll be made in the shade.