Someone help me choose a bra...!!!

It looks to me like it might already have a bra sewn in, if not they will probably be able to do this for you. Try the dress first and then worry about underwear.

You can still get bras that have an 'invisible' back that do up at the front and just have a see through back.

The stick on ones might work for someone with a smaller chest as they don't really offer much support and I have no clue what there staying power is like. Wouldn't want it to fall off on the day.

The clear ones would be easier but since the back is transparent it might show up, you can take one and see if it's visible underneath.

Another option is to buy a strapless bra that has a lower back and you can also find some corsets/basques with a low back.

Those horrendous stick on things are no good unless you are very small chested. More suited for those that don't even need a bra.

You can get clear shoulder straps, which I doubt you'd see under the lace of your dress, and also clear back bras, if you don't need the shoulder straps for support.

https://www.debenhams.com/webapp/wcs/stores/servlet/prod_10701_10001_152010113199_-1

https://www.debenhams.com/webapp/wcs/stores/servlet/prod_10701_10001_152010881786_-1

Brilliant these are all really helpful, thank you ladies, I'm going to try a couple I think with the dress to see what works!