Ok, this can be hard and can be mild. First thing to know is never sacrifice being hit for a balloon, it says it adds 3+ but really it's 5 because of the 2 second stun afterwards.
This sometimes luck based, you can have 7 balloons at the start or you can have 3 all this matters!
As you start off don't ever attempt to the get the first or second left balloons, you'll never get them and you'll miss out on some balloons which are vital. After you feel happy enough with the cliff, always make an inside turn but be very careful you don't get stuck on the cliff edge! Now the next part you need to aim to never get hit and if you do get hit you can only be allowed to be hit up to two times! (unless you're getting a base time of 34-35.)
Now on this open bit, try not to dodge wide, you'll cost time going back in, I try and stay on the right side for some reason the invisible doesn't effect me as much here; which is very important because the walls make you bounce which can cost up to a second!
The final stretch I find really hard, it seems narrow and sometimes if you're far ahead you can cross paths as the AI's birds are coming which is bad. So if you get hit make sure it is twice, try and stay on a side and dodge to the opposite side that way, you'll risk the wall and you may run into a balloon as well. I did this twice and got 00.0 both times after hours of trying.
My scores are :Balloons 13 Balloons 15
Birds 0 Birds 2
Time 35.5 Time 36.7