First check netting is the right way around and not inside out as it would be too tight. The right way around is, netting to inside, pole inserts to outside and at the entrance, the clips are to outside.
Next insert part of pole into each of the pole slots on the trampoline.
You might need a ladder to help with this part depending on the height of the poles on your trampoline. Do not pull any individual one all the way down, otherwise the last ones will not reach the top.
Next, when you get all the netting started on all poles, it will look something like this then, you can put each down bit by bit from standing inside the trampoline.
Lastly, tie the straps that come at end of the trampoline netting around the frame and hook onto the trampoline jump mat eyelets or suitable secure point.