I use to forget the combos so I made the macros more to remind me of the combos without going through the ability menu. You SHOULD NOT use macros for ninja mudras as it creates a HUGE LOSE in DPS, and they take much longer to cast. Here's what a macro for Doton would look like though. ^^

/macroicon "Doton"
/action "Ten" <me>
/wait 1
/action "Jin" <me>
/wait 1
/action "Chi" <me>
/wait 1
/action "Ninjutsu" <me>