First of all, you need a good reference for distance. Take the width of your thumb and line it up with the side of your E6B or a ruler that indicates nautical miles, you will need that when determining your distance. When you know where you are going to divert through, use the side of one of your fingers or hand and draw a straight line from where you are to your destination (simple enough you already know). You got your track, now, use your thumb and measure your distance. You got your distance. To find your approximate heading, my pre-flight test instructor told me this, take either your thumb or your pencil and line it up with a track line, then without twisting it, move it over a VOR station (we have the odd one here and there in Canada, not so much, but im sure you have plenty of them in the states... if your from the states

Do your 5Ts, (turn, track, throttle, time, talk), have a glance at your fuel, tell your instructor that you would tell flight services or whatever that you are diverting, and go for it
