Help needed with a cover up for the beach

[FuglyDucking]

I have finally succomed to buying a swimming costume for the summer. Have gone for a black all in one with two small stripes across the middle/just under the bust. Although I have fat flabby arms I've decided its too hot to care. HOWEVER, I still care about my fat flabby thighs and podgy tummy, so I am looking for a way to cover up my bottom half from about waist down to about knees. Would prefer if it was something I can swim in although its not a must

Any suggestions?

TIA

Anyone?

Sarong?

It IS too hot to care.
And when you get to the beach, you will realise that not everyone looks like a model from BB, and they are all simply enjoying being out and in the sea, too.

Wear a sarong for walking about in. Folded in half to make it shorter.