My favorite glue of all time to use for hair bow making is a high temp/high heat glue gun with high temp glue sticks. You can find these at any craft store and they are just a few dollars. The photo below is the gluegun I use and I purchased at Michael’s:
The only issue to be aware of when using the higher temp guns (you can also get a regular gun or even a low heat one) is the increased chance of getting burned because of the higher temperature used to melt the glue.
Hot glue finger caps will be life savers for you when working with hair bows and lots of hot glue. Here’s what I’m talking about: Mod Podge Hot Glue Finger Caps Especially when using hot glue for flower hair bows, you’ll want to be very careful to not burn your finger tips. I’ve been using hot glue for bows for over 3 years now and haven’t burned myself until recently. Let me tell you, the burns were BAD. I got blisters there and it burned for days. Be VERY careful working with a glue gun so the same doesn’t happen to you and also consider the extra few dollar investment in the finger caps. They are easy to work with once you practice a bit and will save your fingertips from the potential burns.