Using a metronome* while playing can be helpful in many ways, like keeping your song tempo consistent and improving chord changes, notes and rhythm patterns. Try using this one (video) or download the free Pro Metronome app on your device. Start out by changing simple chords on the tick sound, at a slow tempo, then faster tempos. As you become more comfortable with the concept, then move on to songs, rhythms patterns, etc. Timing is everything! 
Play on…
Marlene

*To hear more about using a metronome, and other cool guitar info and insights, listen to my newest podcast, Guitar Friends interview with Preston Huber ~ episode 33!