Be Firm Leaders will always find someone who is not willing to follow general rules, or balk at orders.  They will have to be firm and insistant to get complaince.  No team or group or nation has completely agreed with its leaders, however, the leaders were chosen or made for the purpose of doing what's best, or right, not necessarily to make everyone happy.

Be Fair.  Although leadership means to be firm with decisions, that doesn't mean that a leader is always right.  Someone may have a different view, or an alternative option which might better suit the group.  A leader needs to know to listen.

Be Humble.  Leaders of every nation and organization have found that arrogance will not only get them killed, it will destroy every ideal they work towards.  Any leader who believes they are invincible, or cannot be stopped will soon find his charge in ashes.

Be Consistant.  Nothing is more frustrating than someone who constantly changes their mind, or ideals.  If your off to fight for one cause, dont abandon it completely for another.  Keep your decisions on a consistant level.

Be Thoughtful  Think before you act, consider every angle.  Never ever walk into something without at least two ways out.  Never ever enter an agreement you cannot get out of.  These things will keep you clean, and safe.  Even in the face of danger, always make sure you have backup.

A note on villain leaders:  Villains come in all shapes and sizes, in groups, or alone.  The above statement pretty much covers heroes, however, villains were never known to play by the rules.  Often it is survival of the fittest.  Subjugates who fight back are often done away with.  A villainous leader cannot handle competition and will do whatever it takes to eliminate any threat.