Play the note written as middle "C" on your instrument.
Play a middle C on the piano or on the pitch pipe. If the notes are the same, you have a non-transposing instrument.
Match the note your instrument is playing as a written "C" on the piano or pitch pipe, if your instrument is a transposing instrument. The note that matches indicates what key your instrument is in. Some lower-pitched instruments, such as bass clarinet, are written an additional octave higher in addition to their transposition.
Calculate the interval between the key your instrument is in and C. For B-flat instruments, the interval is a major second down from a written C. For E-flat instruments, the interval is a major sixth down from a written C.
Ask your conductor or band leader for the frequency being used for A. This can range from 432 Hz to 444 Hz, but 440 Hz is the most common frequency used. Calibrate your tuner for that frequency for A.
Transpose the A to the note that will sound as A on your instrument. For the alto saxophone, an E-flat instrument, play a written D-flat.
Tune your instrument according to the instructions given by the manufacturer.
Transpose any requested pitches to the note that will sound that pitch on your instrument. For trumpets, if you are asked to play a concert C scale, play a D scale, a major second above the requested pitch.