I understand you're wearing a makeshift diaper. Diapers I've come across for daytime use (Depends and store brand, Tena, Seni) tend to be thin and quiet. Adult baby and nighttime diapers (my comment for Dry 24/7 is "king of crinkle butt") are thicker. If they make too much noise, you can wear underwear over them to mute them a bit, but there's not much to do about bulk aside from wearing looser clothing. If you're still using those, did you have to use so much absorbent materials that the bulk is sizable?
My first time out I was standing in a line and was constantly fretting if the guy behind me could see them. Then I realized that he probably thought I just had buttocks fat if he looked long enough. Even if he did figure it out, you'd have to have lots of guts or little social skills to admit you were staring at another guy's butt.
For noise, if you really want to know, audiorecord yourself walking with clothing and some light background noise and play it back (not through headphones!). Your body conducts sound, and your brain can even be filling in gaps (you know diapers crinkle, and you can feel them crinkle, so you "hear" them crinkle).
For the funny waddle, Seni actually has an instruction on their pack for that: fold the diaper into a 'v' longways to make a trough. When I push my legs together, I mostly either get a 'v' or a 'w' shape. The 'v' is better for keeping liquids from spilling over (at least while standing), plus it puts less material in a line between your legs.
The biggest advice. Most people [I run into] only notice things they care about, and they only care if they have reason to. If you are acting nervous, people will try to figure out why. Around people you know, they will notice differences in behavior. Don't look nervous, or like you're trying to hide something, or like you've really gotta pee... just look normal. People won't have reason to notice, so they won't.