Spanx or other that will make me (specially my arse), a dress size smaller

[nigelforgotthepassword]

....I'm generally a size 10 with a bit of a belly I want to pull in-nothing too disastrous-but more notably a size 12 arse that looks like a bag of porridge in a pretty Snug lace dress I want to wear to a ball in 5 weeks time.
I can lose a bit of weight before then but I'm going to need something sculptural to make my arse look less lumpy and fit in the frock-Spanx or similar...
Do they work? Are they worth it? Do you buy your own size or the size you want to be?
Dress is a Bardot neckline so whatever it is has to be strapless ideally...
Ta

I've ordered the tights marzipan...
And I'm about to get on my stepper for 45 minutes before work... I knew the bum fat would catch up with me one day-it runs in our family-but it seems to have happened over night-I thought at least it would be a gradual thing

Loupgarou...but could you actually breathe?!

Spanx have an 'assets' range that does wonderful things for your bum.
I've got similar proportions to you, and normal Spanx make my bum look like a pancake.

I have those tights, they are fabulous, smooth everything out and last for ever.

Good luck Nigel, I'm sure you will look fabulous!

Spanx smooth the bumps if they're incidental but don't expect sylph-like transformation! Beware of overhang (back fat) and having to tug "foundation garment" up or down when standing after sitting. Ugh!

Wear something you feel comfortable in so you can relax and enjoy yourself. From one who knows... been there, done that.

I think Spanx cycling shorts do reduce the size (slightly) rather than just smoothing. Had to have a bridesmaid dress altered when I went for a fitting wearing them!