How to apply self adhesive wallpaper without messing it up?

This link has lots of hints:

https://livetteswallpaper.com/blogs/wallpaper-101/removable-wallpaper-dos-and-donts-how-to-install-self-adhesive-wallpaper

This may help: https://www.justmeasuringup.com/diy-wallpaper/

Hi Desiree: Very carefully! :) First, make sure the wall is clean and dry. Preparation is the key to a good job. What I do, after making sure that the sides and top are square, and that there is a straight line down the wall to make sure the paper is straight, is to stick some painters tape all along the ceiling next to the wall and then I stick about an inch of the paper onto this, making sure that the side edge of the roll is even with the line on the wall. Then, I unroll it from the backing about 6 inches, checking the line, and using a wide blade plastic putty knife, smooth the paper out. I keep doing this all along the wall. You don't start in a corner, but paper around a corner. Then, when you're all done papering, use the putty knife to cut the paper at the ceiling, putting the putty knife on the wall up to the ceiling and using a razor or whatever you have, to cut the paper. If you do get an occasional bubble, you can stick a pin in the middle of the bubble a couple of times and squeeze the air out.

Here are a couple sites that should help:

https://www.youtube.com/watch?v=gRpZ2bMojts

https://www.homedepot.com/c/ah/how-to-hang-peel-and-stick-wallpaper/9ba683603be9fa5395fab901d66778b

https://www.wallpops.com/how-to-hang-peel-and-stick-wallpaper

Good luck

Very slowly peel the backing and apply at an angle. I use a damp cloth to run out the bubbles as I go. Also a good plastic squeegee will help to ease the bubbles out. Don’t move forward until you have worked out all bubbles and creases. About an inch at a time.

Here a good link for you:

https://abeautifulmess.com/5-creative-ways-to-use-peel-and-stick-wallpaper/

How to Install Self-Adhesive Wallpaper in a Snap!

https://tidywithstyle.com/self-adhesive-wallpaper/

I start at the top and I don't remove all the backing until I am rolling it out on the wall. I go slowly and use a credit card or other stiff tool to remove bubbles as I go.

I also do exactly as Homeroad does and it works very well. Main thing to remember is to not rush but to take your time in affixing the paper and then pulling a little bit of the backing material away at a time.

We just did this in our pantry! Here's the entire DIY, but the short of it is, measure well, go slow and make sure your walls are really clean and smooth. https://www.exquisitelyunremarkable.com/2021/06/how-to-put-up-peel-and-stick-wallpaper.html

Line it up using Plumb guide lines. Unroll without stretching a bit at a time. Use a flat edged smoother to remove bubbles as you go.

Measure the wall so you have a streight line to follow from ceiling to floor follow that line

heres a vid to help you out, a extra set of hands wouldnt hurt either

This stuff is tricky for sure, likes to stick to itself and tears very easily so really, the best tip I have is to go slow. Only remove as much backing as you need at a time.

apply in stages ..remove backing as you are ready to attach to wall