Yeah, I use a spray bottle with a dishwashing liquid solution in - spray that on both the seal and the suit to make sure they slide together easily. For the wrist seals, I find it easy to have my suit hanging up (that's just something I've found works), and then, pushing on one side of the seal to distort its circular shape, lift it into the sleeve so that the grooves on the seal and on the sleeve line up. By releasing the outside of the seal, it should pop back into its natural circular shape and hold by itself in the sleeve. I then put my fingers through the wrist opening and push the seal into the grooves on the sleeve. I then work around the edge, pushing the grooves together, and with the soapy water it slides into place fairly easily. Be sure to listen for the 'click' as the seal sits into the groove on the sleeve. Confused? You will be!
The neck seals are a bit more problematic in my view but work in a similar way. You have to get the seal between the 'lips' in the suit, and then trace it around in a similar fashion.
In both cases, work around the edge systematically. As long as you have positioned the grooves appropriately, they will find their own way.
Good luck!