Even if you are only dating for fun and aren't interested in something more serious, you still will have more luck (and probably more fun) if you have some "ground rules" set up first.
I don't mean that you have to do a big list of rules or anything like that, I just mean do what you can to ensure that you and your partner know what you each expect and want from each other and the relationship.
The term "dating for fun" may mean one thing to one person and something quite different to the other. To make things easier for both of you and to reduce the risk of hurt, strife and misunderstandings, just talk about what you expect in a relationship.
Here are some things that I mean, some things that you should probably decide for yourself what you want or don't want, and then talk that over with whoever you date so you are both on the same page:
1. Fidelity. This is huge. Many people who are just dating in a causal relationship may also think that means that they don't have to be faithful. They may think that they are still basically a free agent and can do whatever they want to do.
Spelling out your expectations right from the very start, can be a little uncomfortable but it can also save a lot of issues down the road. After all, if you are just looking for fun, you want to have fun.
You sure don't want to have to deal with a lot of complaining and fighting because you thought you could date other people but your dating partner thought that you shouldn't.
2. If you both agree that you don't have to be exclusive, are you going to share your exploits with each other or will you keep it to yourself? Are you sure that neither of you will feel jealousy? And one other thing, both genders are very capable of feeling jealousy no matter what they say.
At the end of the day, and at the risk of sounding sexist, sometimes men can sometimes have two different standards. They may think it's perfectly ok for them to date multiple people but they will often think poorly of any woman who dates a lot of men.
If that describes you, you really should take some time to evaluate the type of person you are. If you are going to judge someone for doing the exact same thing you are doing, that doesn't speak that highly for the type of person you are. Don't tell someone that you don't care if they date others and then turn around and have a problem with it, that's not fair.
So, dating for fun can be… well, fun. But, unless you are honest and open (with your partners as well as with yourself) about what you want, don't want and what you expect, you will most likely have less fun and more stress. It's extremely important for both of you to be on the same page about the specifics of your relationship.