I like shots first thing in the morning when I wake up - less margin for forgetting after a busy day because you get it right out of the way from the beginning.

Anyway,

Go in with the needle fast like a dart, but inject very very slowly. Take your time, take 20 seconds or more for half an ml if you need to. You'll find less PIP and soreness this way. Run the syringe under some warm water before you pin - that helps too.