When I taped my seams, I had an occasional air bubble with the 2" tape but none with the 4" width. The 4" wide tape was much easier to deal with and doesn't seem to slip around as much.
On vertical seams, I tacked the tape with a temporary wire-sized nail at the top to help hold it in place until it was almost dry and holding well. I used a cheap plastic spatula to even out the tape and scrape out the air bubbles.
The other thing I did was I lightly wet down the seam area with epoxy just before I applied each piece of fiberglass tape. Other than the tacking, I think that may have helped me the most.
It will be interesting to learn what others did with their tape applications.
PS. CPES epoxy is not recommended for the tape. I used Doc Rot's Layup and Laminate epoxy for my fiberglass tape, which is a mutually responsive product. Please consult the manufacturer of your product to know what is best to use.