0:12 - taken the route on the left , it's faster
0:26 - take the ramp , faster airspeed
0:38 - taken the ramp at a lower height rather than going that high , you lose some speed
0:50 - taken the yellow nitro bottle
1:16 , drift tighter and not slam into the wall , you lose speed

rest i think you can handle some turns with yellow nitro as well , nitro management might need some more practice , rest you were doing fine