For me, the secret (after learning proper lathering and face prep) is to always, always use light pressure. Even though I may be tempted to use more pressure on a particular spot, I resist that urge and simply approach the hairs from a different direction. My secret to getting a BBS shave every single day is simply by knowing, in minute detail, the grain of my own face. Once I know that, I maintain a nice, steady pressure all over, even my neck. Thinking I had sensitive skin, I used to get terrible razor burn. I don't know if my skin has "toughened" or my technique has improved but I know that, unless I use too much pressure, I never get razor burn anymore.
Hope that helps.