Ideally you would set up a bunch of different "states" for your character. and assign him a variable called "state".
if: state = "walking" -> do walking animations etc.
and make seperate conditions for each state he might get into.
this allows you to group a number of actions together and he will be able to do lots of different things depending on the movment required and which animation needs to be played.
then one simple way to pick which state he'd go into randomly is
every X seconds - set enemy.state to = choose ['walk', 'sleep', 'run', 'pushups']
so it will randomly throw him into a new state every x seconds.
or base it on other conditions like.
while enemy.state = "walk" -> every 1 second, add 1 to enemy.walkingsteps.
if enemy.walkingsteps > 100 - set enemy.state to "sleep"