If this is your first visit to Mull it may also be your first encounter with single track roads. They can be a bit daunting at first, but you'll soon get the hang of it if you follow the code.
Passing places occur frequently. Most are marked by a black and white banded pole, although some have the newer diamond shaped reflective sign which is easier to see at night.
Think of passing places as very short stretches of twin-track road, and you'll avoid most of the pitfalls.
If you're not all that good at reversing, it would be a good idea to get some practice in before you come to Mull.