So you now have your sport-pilot certificate and you're itching to go flying. Any old excuse will do. I'll cover the most popular ones in the next two sections. Meantime, here is the most important one: honing your flying skills.
Remember, all pilots are really student pilots—until they quit learning. Your sport-pilot instructor has given you the tools to fly safely, but you're not yet an experienced pilot. Even though you may legally take passengers flying you might decide to wait until you have more flying time in your log before you do so.
The pilots with the highest accident rates are those who have just received their pilot certificate. It's similar to new drivers who have the skills to drive safely, but don't have the experience needed to keep out of harm's way. That takes plain old practice. Fortunately, practicing flying is even more fun than practicing driving.
Until you're more comfortable with flying and have learned to make needed skills your responsive instincts you probably will not plan many longer flights. In fact, you might decide to simply "fly the patch" or fly in the vicinity of your home airport. That's a good idea. Practice touch-and-goes, fly the airport pattern, then venture out farther. If you haven't flown above 5,000 ft. above ground level (AGL), give it a try. Just remember that sport pilots can't legally fly higher than 10,000 ft. above mean sea level (MSL) or 2,000 ft. AGL, whichever is greater. You can inspect clouds at a safe distance.
Flying requires, by definition, stretching your comfort level. You probably weren't fully comfortable making your first solo flight, but you learned what you can and cannot do. Now that you have your sport-pilot certificate you continually will be adjusting your comfort level with new skills and experiences. Learn a little, test a little, learn some more. That's one of the fun parts of flying. Just make sure you don't push yourself too far toward dangerous mistakes. Remember, this is sport flying.
Another fun thing you can do is wash your aircraft. Just as you do when buying a new car, you might decide to wash and even wax your new aircraft frequently. Not only will you be maintaining it, you will be learning more about it. Besides, it's a great excuse to get out of Saturday yard work!