Try running a thin flexible putty knife on top of the tape edge. This sometimes helps even out your tape line because your fingertip really can't reach it since it is concave.

Sometimes when an uneven surface makes masking the area difficult you have to paint then tape. Paint the uneven area of the wall or trim where the old paint is showing as best as you can to cover the old paint before you tape. Yes, you probably will get some wall paint on the trim paint or vise versa but this will be fixed. Allow the paint to dry thoroughly and re-tape this area. Paint the area carefully and remove the tape. You should now have a straight line of new paint with the old paint covered.

What I do is paint the trim first and let it dry. Then I dry brush a little of the trim paint into the joints where the trim meets the wall surfaces-I don't want to build up any thickness, just get the trim color out onto the wall a tiny bit so that when I tape off the trim I can still see the trim color peeking out onto the wall. Now the wall color can go on and you don't see any of the old wall color.

That is exactly right trk65 and something I didn't think of. I actually lap the trim paint about an inch onto the wall surfaces.

Thanks for the suggestions. They seem so simple I'm almost embarassed that I didn't think of either of them. I'm definitely going to give then a try.

I'm sure you will have a nice paint job.