The maker folds the 2 raw edges to the middle - so you would cut your fabric 2", for the 1" maker. I find that slow and steady is the trick. I've only used smaller ones (1/4" bias tape), so I don't know if it's harder or easier to get the 1" to look good, but 2 things I figured out:
1. you need 3 hands
I finally figured out to hold the maker in my left hand, the iron in my right. Then I place the iron on the fabric just as it comes out of the maker. Draw the maker back a couple of inches (or even less, on stubborn fabric), slide the iron forward, and repeat.
2. if you are applying the clover bias tape double-sided "tape" at the same time, it helps hold the folded edges down and in place