Hold the bugle parallel with the ground in your right hand. Place it at mouth level.
Place your lips against the mouthpiece. Tighten the corners of your mouth so that no air can escape through them.
Inhale through your nose. Blow steadily into the mouthpiece through your mouth. Keep your cheeks in. Don't puff them out.
Practice blowing with your lips held more tightly and more loosely. There are only five basic notes to the bugle: starting at the bottom, they are middle C, E, G, C, E, and G. Middle C is the lowest note you can play, with your embouchure at its most relaxed.
Practice moving from one note to another. Skip between notes ascending and descending.
Touch your tongue to the mouthpiece as if you were saying "ta" to stop the sound. This is called tonguing. It is how you will articulate different notes. Practice tonguing by playing one pitch and stopping the sound in different rhythms.
Work with a method book. A method book will provide you with rhythmic and melodic exercises to help your improve your playing.