Playing the trumpet isn't easy. Unlike pianos, drums and strings, trumpets force you to learn a new way of breathing so you can play correctly. You'll also need strong cheeks and lips. With a trumpet, the player buzzes the lips against the mouthpiece to create the sound. The finger positions, along with the lip buzz, determine what notes are played.
The first thing to do is to get a trumpet, and not any trumpet will do. Some are much more demanding of proper technique than others. It's best to start with a student trumpet that's made for new players. Consider a trumpet rental before you buy, to make sure you like the weight of the instrument and the action of the valves and tune sliders.
To begin playing the trumpet, first concentrate on your posture and the position of your fingers. With your left hand, hold your trumpet by the bottom of the valves. Then put your left thumb in the hook and your pinkie finger in the ring at the end of the trumpet.
Next, position the pads of your right index, middle and ring fingers on top of the valves. Wrap your small finger around the hook adjacent to the valves. Once your hands are in position, sit or stand up straight and breathe through your diaphragm. Get a feel for the right posture; it makes breathing easier, which is essential for this instrument.
Getting an actual sound from a trumpet is a real challenge for beginners. Put your mouth on the mouthpice and form your lips as you would to say the letter M. This is the correct position for your lips. Now, make a buzzing sound into the trumpet. Keep at it until you hear sound from the other end. Your first note is usually a C or a G; C is the lowest note a trumpet plays with its valves closed.
Before you use the valves, master sustained notes without them. You'll want to hold a note and keep it even for at least 30 seconds. Once you can do that, you can start using the valves to play different notes. You should practice at least 20 minutes a day in order to become proficient.
You can do a few exercises away from the trumpet that will help you play better.