A tip for singing and playing...
I was working with a student today in a private lesson and their singing and playing weren't syncing up... So we broke it down as follows: 1. Drill the line of chords: D A Bm A | G G A A 2. Eliminate any gaps in the chord changes e.g. the A to Bm could be tricky 3. Keep focusing on the chords & strum while briefing only "thinking" about the lyrics 4. Then do a "dance remix" type thing where you only sing the first 2-3 lyrics of the line and keep your full focus on the chord playing! ..this means we are training our brains to prioritise the chords/strum. 5. Continue to add on more lyrics bit by bit, each time you get something working, repeat it a couple of times, so you are continuously expanding out the line with solid singing and playing. Hope this helps, if you would like to me demo this on a video comment DEMO below this post and I'll do one up!