AutoMark allows you to quickly mark your current target with your assigned raid icon so that your DPS will always know what to attack. It will avoid overwriting raid marks with a higher index allowing your offtank to automark as well. Now you'll know at a glance who is tanking what.

Usage

/automark <raid icon ID> /am <raid icon name>

Create a macro with a frequently used attack and the AutoMark command as follows:

#showtooltip /cast !Heroic Strike /automark 8

It is important to note that Skull will replace Cross and all lesser marks. Your main DPS icon should always be Skull.

Raid icon index

8 - Skull 7 - Cross 6 - Square 5 - Moon 4 - Triangle 3 - Diamond 2 - Circle 1 - Star