the easiest way I’ve found to do it is fold the bottom half up towards the top. Stretch it out with both hands sideways- then slide it over the glans. From there you can just unroll the rest the
sleeve like a condom.
If you’re really struggling at first a little lotion etc on the glans can help it slide past. The
sleeve is also very tight at first. It’ll stretch out over time.
tough to say if you should cut it- mine folds up a 1/4 inch or 1/2 inch- little bit but it’s not a big deal.