Using single notes is a great way to add more expression to a chord progression. On the advanced level of playing you could do sweeping arpeggio runs, use octaves or go all chromatic with some passing tones. If you're not at that level yet you might like to start learning how to add more colour to your chord progressions
The two examples in today's music lesson show simple approaches to moving between chords. This first exercise below is only two bars long. Repeat it a few times if you like. In this example a chord is played and then a few choice notes lead into the next chord. The brief three note melody is virtually the same in each bar except for transposing to match each chord that proceeds it.
The next idea uses a repeating four note walk that leads into each chord. It does not vary according to the chord it is walking into. The melody always remains the same although the chords change.
In your own playing borrow a few notes from the scale of the chord you are currently playing and see how you go coming up with ideas on how to walk into, or out of, that chord. It's co-incidence that both progressions here are in minor keys. Of course, you can do the same for Major keys as well. The idea works for all styles of playing.