Choose one that suits best for you:
-Negative Chin-Up
-Chin-Up
-Pull-Up
-L-Chin-Up
-L-Pull-Up

Use following template for sets and reps:
3x1r, 5x1r, 3x2r
4x2r, 4x3r, 5x3r
4x4r, 4x5r, 5x5r

Notes:
Rest app. 90s.-120s. between sets.
If you're doing Negative Chin-Up, 1 rep is 5-10s descent.
If Negative Chin-Up is too hard for you, choose alternative from here.