Nothing will put weight on a skinny guy faster then the good old school 'test deca dbol' bread and butter bulking stack.
http://www.evolutionary.org/testosterone-deca-durabolin-dbol-cycle
To keep water retention to a minimum it's going to be crucial to run an AI and anti-prolactin drug with the cycle.
Here's what I recommend:
Weeks 1 - 16
testosterone 500mg/week
deca 300mg/week
aromasin 12.5mg every other day
cabergoline 0.5mg E3D
Weeks 1 - 6
dbol 30mg/day
N2guard 7 capsules/day
After your cycle run the perfect PCT protocol:
http://www.evolutionary.org/the-perfect-post-cycle-therapy-pct/
You can order everything you need for the cycle and the PCT protocol from ag-guys.com, n2bm.com and sarms1.com.