I must confess I never had great experiences in the salon (well, they were all pretty bad), so I tend to like to handle everything with my hair myself. That way I know for sure my hair and I won't get hurt by rough combing.

So, to answer your question about trimming...you can trim your hair yourself if you feel up to it. I actually used to have friends trim my hair for me all the time (back in the days when I was trimming my hair).

I'd suggest wetting your hair, comb it out with conditioner in it (preferably with a Denman to help form your curls). Then pick up each curl, and hold it firmly between your thumb, ring and pinkie finger, and your pointing and middle finger. This helps stretch out the curl so you can get to it. Then give it a snip (with sharp scissors, if possible), straight across the ends, near the end of the curl. Make a "T" between the hair and the scissors when you snip. Take off much less than you think you should, because curls shrink up to a fraction of their wet length when dry. It's impressive how much they shrink, so be very very careful. Go slow. It's better to cut too little than too much.

When you finish a section, pin it out of the way. Lift up curls on either side of your head from time to time to make sure both sides are even. Make sure your hair stays wet through this process.

Back in the old days when I trimmed my hair, I used to do my hair that way. I even would have friends who knew nothing about hair help me, and they did no damage, while salons can do plenty.