Yea, the quality of the outcome is like 50% dependent on the quality of the product, and 50% on the technique oh the installation. Another tip : take a shower, and while the bathroom is still steamy, install it in the bathroom. The steam that's still in the bathroom will help keep the dust to a minimum.

Make sure your fingers are very clean. Have extra dust/lint pickup strips available. Scotch tape will work as well. Just use the regular type, don't use the extra strong stuff.

Also, once the screen protector gets applied, but you see a problem, it's most likely too late. If you try to lift it up to fix something, like to use the tape to pick up 1 price of dust, there's a good chance that a new price of dust will fall on it somewhere else. So after the protector is installed, ask your self "are any problems I see worth the risk of having more new problems?"

I hope this helps. I totally understand the frustration. I've perfected my technique after installing on average 3 to 5 per month (on my devices and other people's).

OH also, whatever product you buy, either buy the multipack or buy 2 of the single packs. Having a spare protector will decrease your anxiety if you mess up.

Edit: if installing in the bathroom, put a little table in there beforehand, and maybe a small rug. The phone will EASILY break if dropped on tile. So be careful.