Melee Enemies: Wack enemy. Wait for enemy to move forward for 0.5 seconds or so. Wack enemy.
Ranged Enemies: Circle Strafe and wack enemy.
Exploding enemies: a) Use bow and shoot until dead. b) Run in. Wack enemy. Run out as fast as possible.
Special Enemies:
Spider Jockeys; Use a bow, or traps. Exploit the fact that the spider can let the skeleton suffocate in a 2 high room, and kill spider like usual.
Ghast; Wait for it to shoot a fireball at you. Punch fireball back at ghast. Use bow and arrows to shoot Ghast.
Helpful Tips:
With the creeper, you have 3 seconds to get in, wack it, then get out.
Always back yourself into the corner of a room that has a roof if fighting melees (If possible, if not, circle strafe and wack whilst stepping back and forth) to avoid getting flanked by multiple foes.
Do not let a Ghast get too high. You will be unable to shoot high enough to hit it.
Ghasts can see and shoot through lava, beware.
Ghasts cannot see through glass.
Ghasts shoot at the camera, not at the character. Go into third person view mode, and angle the camera correctly, and the Ghast will not shoot your character.
If you attack 1 Zombie Pigman, all Zombie Pigmen become hostile.
The reach of your attack is greater than the reach of a mobs. Thus, building a 1 high wall around you (I recommend a 2x2 room inside these walls, and if your feeling cautious, a block one block above [not on top of, but a block higher than that] the wall blocks, so the mobs cannot jump over the wall) will allow you to attack mobs without it being possible for them to attack you, in one of the safest ways possible (Barring staying behind a door or on top of a pillar)