What kind of camera is this? If it is just on the outside of the lens, you can use a lint-free cloth (like a glasses-cleaning cloth) and just wipe it off.
If it's a DSLR (or anything with a replaceable lens) and it is on the mirror or on the sensor, you can use a
handheld blower (don't use compressed air). If you can't get it out and aren't comfortable trying to clean the inside of your camera, take it to a shop and have it cleaned. It isn't very fun, but it's better than having to get it repaired. It's very easy to damage parts inside the camera once you open it up.