Instructions
Launch "World of Warcraft" and select your character to enter the game.
Press "Esc" to access the main menu and click "Macros."
Click "New" at the bottom of the macro window. Select an icon and a name for your macro and click "Okay."
Click the box at the bottom of the macro screen to begin writing your macro.
Type your cast sequence macro into the box in the following format: "/castsequence options resetcondition spelllist." Replace options with any variables, such as flying if you are going to use this macro while flying. Replace resetcondition with the condition that resets your macro, like changing targets, and replace spelllist with the list of spells the macro uses. An example of a cast sequence macro looks like:
/castsequence reset=target Hunter's Mark, Aimed Shot
This sequence casts Hunter's Mark first followed by Aimed Shot and resets back to the Hunter's Mark spell if you change targets.
Click and drag the macro icon, located above the macro editing box where you wrote your macro, to your toolbar at the bottom of the screen once you have finished writing it. This icon is the same that you selected in Step 3.
Click the icon on your toolbar to activate your cast sequence macro.