Common practice is to tune batter heads (the striking side) to a slightly higher pitch than the resonant head (the bottom side), which makes the pitch bend downwards as the sound decays after striking the drum. Tuning is mostly about getting the drumhead at an even tension at your desired pitch, which will be up to you: the higher the tension, the higher the pitch. To tune, seat the head properly, making sure that it sits perfectly flat and even on the edge of the drum and that the tension rods are finger-tight. Lightly tap the drumhead at each tension rod about an inch in from the counterhoop, and slowly tighten them with a drum key. It's common to move across the drum to the opposite tension rod from the one you started, then to an adjacent tension rod to the right or left, then across the drum again to its opposite, repeating as many times as necessary until all the tension rods have been tightened. What you want is for the pitch at every tension rod to be the same: go to every tension rod and fine tune it from one to the next. It's recommended that you tune the bottom head first before flipping the drum to use the same tuning pattern on the batter head. Note that bass drum heads are tuned much looser than toms or snare: just tight enough to get rid of wrinkles on the drumhead is usually enough. At the end of the day, it's about taste and getting the right sound for the gig: don't be afraid to experiment!