It entirely depends on your body, the type you get and the dosage you get. When I was on 5% cream, I noticed an IMMEDIATE increase in my sex drive, within a month or two I noticed clitoral growth, and by the end of the 6 months I was sprouting happy trail hair and chin hair. Now that I'm on .5% cream (yeah, huge difference), I'm hardly noticing anything. My doctor lowered it because I was having issues with irritability, but this dose is ridiculously too low for me. I'm going to call and see if I can get a higher dose with my next bottle but I'm afraid it's going to cost a lot more :'D
When starting (on a proper dose that is), expect a change in your mood patterns and sex drive first. Acne comes next, around the 2nd month usually. The rest depend on your body/dose/type. Hair growth and voice lowering tend to come around the same time, and it seems like hairline changes come slowly.