You can never say enough about the importance of playing in time or keeping good solid rhythm. Using a metronome is one of the best ways to help master this ability. Metronomes click at a set pace based on beats per minute (bpm). They generally range from 40 bpm to 250 bpm. They can also be set for different time signatures. This puts the accented beats in the right spot for the appropriate feel.
Using a metronome at first can be very frustrating as they are very unforgiving. When playing and practicing by yourself you don’t realize how much you speed up and slow down. This tool will remind you of even the slightest inconsistency.
The trick is to start slow and simple. In the beginning you may want to set your metronome at fairly slow pace and just listen first. Once your mind is locked into the beat you can clap, tap your foot, play just a single note or anything simple in time with the beat. Match each click and you’ll be clapping, tapping, or playing perfect quarter notes. Once you get the hang of this try 2 notes per click. Now you’ll be paying perfect eighth notes.
When you first start playing actual music with the metronome start with something you know very well. This way you can focus on the timing without having to think so much about the notes. Like so many things, the more you work with it the easier and more natural it becomes.
Aside from training you to have impeccable timing this will also help you to mark your own personal progress. Play scales, arpeggios, riffs or any musical passage with your metronome. This lets you see at what tempo you can play these clean and evenly. Start slow and as you get more comfortable increase the bpm to push you to the next level.