Choosing a clown character usually begins with understanding the traditional types of clowns. Not all clowns wear clown noses, so connect the type of clown you are basing your character on with the traditional "nose" worn by that clown. The most common clown today, including most circus clowns, is the Auguste -- a clown who is known for his trickery, pranks and outlandish costumes. This clown usually wears a wig and red nose; if you are creating a circus-style clown, or Auguste, you will definitely want to include a red nose. Other clown types, notably the White Clown, often don't wear any sort of nose, and might paint their nose white (along with the rest of the face) or even black.
If you're a clown who plans to perform acrobatics, juggling or who will be taking a pie in the face, you should make sure your nose can stand up to the activity. A clown nose on a string or one applied with adhesive will work best under these conditions. If you will be performing in front of a huge crowd, use a large, oversized nose or one that is glittery or lights up. These will be seen easily by the audience. When performing in a group, choose a nose that allows you to blend into the whole, or one that allows your character to stand apart from the crowd.
Your clown nose might need to make it through one event (Halloween or a costume party), or you could be planning a vast number of appearances as a clown. Your nose should be durable enough for the specific circumstances. For a one-time event, go for an inexpensive nose, such as those made of foam that simply clamp onto your own nose. No adhesive or elastic are necessary for this type. If your clowning will be a repeated affair, consider noses in a variety of sizes, shapes and materials, such as those available at online distributor Clown Antics (clownantics.com).
There are clown noses that slip on your nose and are held with an elastic band around your head, those that must be applied with a special makeup adhesive, those that simply clamp onto your nose and those that are painted directly onto your nose. Choose the application method that suits your situation and temperament. Kids do best with elastic bands, clamp-on noses or noses that are painted directly onto the face. Professional clowns might choose from a selection of different types of noses with different methods of application, depending upon the circumstances of their performance situation.