Some words can easily be combined, such as:

Fabulous + Delicious = Fabulicious
Brad + Angelina = Brangelina
Spa + Party = Sparty
Crazy + Drunk = Drazy

How can we combine Swim + Sleepover?

You can change "swim" a little if you'd like... for example, change it into "swam", "swimming", or "pool".

Good luck!

ps. I know this is pretty stupid, but I'm quite bored. And, after all, this is polls&surveys, so I guess you're aware of bored people wandering this section.