When I received my first pack of real adult diapers (some Tranquility ATNs) I was excited to tape up and try them out. Well, I don’t know if it’s me or the tapes, but I can’t seem to get this right. After I do my best at taping my diaper, I stand up and it nearly falls off. Then when I attempt to adjust tapes, I rip one off accidentally. Basically what I’m saying is: what are your techniques? How do you get your diapers to snugly fit without pulling out some duct tape to finish the job?
This articlehelped me when I first joined.
I find putting on a diaper is like tying a bow onto a present.
It’ll get better everytime you do it, until you get it perfect.
Practice makes perfect. 
Find a fit that works best for you!
Some like to do it standing up against a wall. Bottom tape, top tape then keep switching. Also, some diapers have resealable tapes. Some don’t. If the plastic tears, use a small piece of duct tape. It comes in colors and patterns nowadays.
I do it lying on my back. Just plop my butt where I want it and seal it up!