Practice firing distance weapons to the left, practice with different doors and monsters to the right.

To fire a bow or other distance weapon, ready it by applying it. (this will unready your shield so be aware.) And then fire by pressing the shift key (the fire key) and then a direction key for the direction to fire in.

Fire a wand the same as a bow, but be careful the spell could hurt you too. Fire and run if the monsters are too close. The drawback of using wands and similar artifacts is that you don't seem to get experience for the things you kill this way.