I figured that I paddle most effectively on my "strong foot" side
meaning that I have better "rail control" on the side of my dominate foot, hence the board tracks straighter on that side.
Practice "rail control" on your weak side... paddling only on that side, "weight" the rail a bit and see if you can improve your stroke count without yawing.
That, plus learning the "c" stroke should help.
Diagram of "C" stroke on the right side of your board:
/ \
| |
| | \ <--- blade angle at catch
| | | <----blade angle at pull
| | |
| | / <----blade angle at exit
| |
| |
|_| <---- board
I am sure there are better paddlers with more technical suggestions..... but this worked for me