I've done the 'first bridling' on a few babies, and from my experience the first time is super easy because they're clueless. After that, they wise up a bit and that's when you get a bit of resistance (sometimes).
Like Phizzy said, make sure the bridle is let down a hole or two so it's easier to pull over his ears. All of our other babies did just fine with any sort of snaffle the first few times. Nova, had to be different, of course. I actually went out and bought a (very expensive!) Happy Mouth D-ring for him which has helped a lot with his chewing. Now he only chews when I'm on him asking him to turn and stuff, but will carry the bit when I'm leading him quietly. I wasn't sure the bit would help, because it's a thicker bit and a lot of horses like smaller ones, but I suppose Booger is just different.
Once you get the bridle on, try to leave it on long enough for him to stop chewing (or at least until he starts to pause between chews, if he's anything like Nova was). If you have a stall/pen you can turn him out in and leave it on that would probably be the easiest. You might not want to do that the first time you bridle him, but at some point it would probably be helpful - I didn't have one to use, but I wish I did.
One thing I learned from Nova - be patient! When he started to get fussy about taking the bit (ie. he wouldn't open his mouth wide enough for the bit to slip in) I started to put my fingers in his mouth, wiggle them around on his tongue, etc. What actually worked in the end was just having one arm between his ears, and the other holding the bit, and waiting him out. It took probably 5 minutes the first time before he'd take it, but every time since then he's been much better. In fact last night it only took a few seconds of thinking before he took the bit.
And one other thing, when you go to take the bit out, try to not let him fling his head up. That scares them (as it did Nova) and you can have a real battle trying to get them to let go of the bit. If you feed Stitch crunchies or carrots or something, try offering it to him as you slip the bridle over his head and off. It worked with Nova.
(Can you tell Nova was the bad child? Lol. He's much better now though!)