1. The single most important item to purchase is a good quality paddle. Be sure to see our Buying Guide for extensive detail on what to look for. To some people, price is sometimes viewed as the only factor to consider. But it is actually far more important to get one that is the right weight and has the right characteristics you need to be successful.
If you are a tennis player with a two handed backhand just starting out in pickleball, you may want to consider a paddle with a longer grip/handle. A regular sized grip may not be what you need to hit those backhands with the pace you are used to generating.
There are many exceptional manufacturers. Reading the product descriptions carefully will help you pick out the perfect paddle. Having the opportunity to try paddles owned by friends will give you an idea of what works best for you.
2. Pickleball balls themselves are either suitable for indoor or outdoor play. They are labeled as such. Because they are plastic, they do break especially when playing outdoors. Therefore, just like any sport, all players should have several on hand at all times. Note, they are not the same as wiffle balls used in backyard games!
3. Your shoes should be appropriate for racquet sports. Pickleball requires quick movements - especially moving from side to side. They also must have the ability to grip the court regardless of the surface.
Therefore, running shoes which are built for going straight ahead, perhaps for long distances, are not ideal. Basketball shoes are built for jumping and landing among other skills. In pickleball, while you may jump from time to time, some of the support and ankle constraints may inhibit your play in these shoes.
Pickleball shoes are specifically designed for this activity. However, good quality tennis or other racquet sports shoes will suffice when getting started.