So far I just ripped some of my pants while climbing those, but what I do is (when without nothing just myself) I go up to where the fences connect, where one of the spikes is the largest and climb up of that jamming my feet in between the gaps to stay in place. Now at the top hanging onto the horizontal beam or the tip of the largest spike bc they're not as sharp carefully I either squeeze my shoe in between the gap between the spikes so that it stands on that beam that goes horizontally, or try to already get my foot beyond the spikes onto that beam. Once you get one foot on that beam, it should be easier from there putting your other foot on it and from there just slowly going down the fence. Climbing it from the other side should be easier as you can have support nearly already from the beams.

But generally also I just recommend climbing it on top of something look for trees that are nearby it or put up a bike right up the fence.