Proper procedure is to wait 30 days for the paint to cure before applying tape.
If you do it earlier than that.....remove tape very slowly as it will probably pull some of the paint off. If it does, use some small artist brushes to touch it up; if it's a very large area, use a small roller to touch up.
Recommended is to just use a high quality angle brush anywhere from 2" to 4" whatever you are comfortable with. If you use a high quality angle brush and go slowly, you can do it without tape; and keep a very damp rag with you to wipe off any paint on the other color. If you can get this technique down pat, you'll be better off
Btw...if you use tape, use only quality blue painters tape or the green frogtape. It is not recommended to use masking tape, as it doesn't remove cleanly and can leave residue on what you taped. It can pull the color out of stained wood.