For update see belowHi you all,
This is my very first upload, so I hope the work I did will please you. A swimmingsuit/catsuit/body.

The design is very loosely based on the type of designs by Marlies Dekkers, a Dutch lingeriedesigner. After some comments of some members here (and thank you for that!) I made some alterations. Playing around in Cas I found out that this swimmingsuit can also be a (bridal) body if accompanied by some lace gloves and stockings or a catsuit with high buckled gloves (i'm still working on them) and boots. The patterns I used are standard EA basic game, because I'm not capable to make my own patterns yet.
So I made 4 variations:
acatsuit with buckles on the straps (the broather type of straps)
swimsuit with broather straps
swimsuit/body with finer straps
swimsuit/body with finer straps, without the extra straps.
Body, straps and sheer part are all recoulerable. So the rest is up to you. (which I think is the fun part of Sims3). Useable as formal, night- and swimware.
Here the downloadlink http://www.mediafire.com/?zyqqvwkgvnzbridalbody

bathingsuit

with buckles on the straps (and sorry thery are in Cas because my game kept crashing) and the gloves I'm working on.

Variation with other pattern, maore swimsuitlike

I hope you like it,and happy simming
UPDATE 14 april:
I heard the above link is invalid. Here is one that is working:
http://www.mediafire.com/file/e6zu6e0m3rsg19o/FA_4variationsDesignSwimsuit2_FranW.rar