You can take it preworkout, if you like. It will help with nutrient uptake during the workout and provide a good pump. If you dose IGF high, it will quickly become uneffective. I've used it at doses from 20mcg to 150mcg. Under 50mcg seems to remain effective for me, for 6 to 8 wks. I have taken it 5x wk, on workout days, and I have taken it 7x, injecting around my normal workout time, on the nontraining days. I found that taking it on workout days only works best for me. You shoudl take your dose all at once.
As for gains, it's hard to say. Everyone responds different and it will depend on your level of development. Overall, I would not expect to gain a ton of weight. Peptides are far different from steroids. You will however recruit new cells, which will hopefully be developed with time. Thats something that steroids are not going to do.