As a coach, I recommend to athletes I coach that they break the race down into three phases:
First phase - approximately 20% of race distance. Go off hard and get your best position (according to your ability). This is at a pace you could not maintain for the whole race.
Second phase - approximately 60% of race distance. Settle into a good, hard, pace, which you feel you can maintain. You should be racing within a group of athletes, with the occasional athlete who went off too fast dropping back, and the occasional athlete who went off too slow running through.
Third phase - approximately last 20% of race distance. Dig deep and try to increase pace. Start this phase from a point you feel able to race harder from. Choose the point before the race begins. Try to "pick off" runners ahead of you.
That's my suggestion.....