It may be worth running through a couple of times just to familiarise yourself with the course. A few things to be aware of:
You'll lose time for missing targets
You'll lose time for hitting civilian targets
You'll want to aim for 100%+ accuracy
Be careful when you hit hostile targets as bullets can pass through and hit civilian targets
There are a couple of opportunities to hit two targets with one shot which will get your accuracy up past 100% (two pairs in the knife room and the last two targets before the exit)