I read again and again that many people have problems with attaching safety eyes, especially those eyes that have a small white plastic disk to fix them.
With a few helpers you can not only apply them very easily but also in such a way that the eyes do not get stuck to the stuffing or are pressed outwards by it.
For easy attachment you need a snap plier (it's the one with the red handle at the picture). This is actually enough, because you simply push the disc onto the pin of the eye.
If you also want a more comfortable stuff, then you need a wire cutter (it is the one with the green handle) and a lighter (I use a storm lighter for it, because with it you can target better with the flame, but a normal one does it too). The tool, which looks like a little thorn, is an aid to "pre-drill" the spots for the eyes, so that they can be easily inserted into the crochet piece.
So: if necessary, pre-drill the spot for the eye with the thorn, insert the eye, put on the white disc and press firmly with the snap pliers. This is really very easy with the pliers, without having to cut in the white discs (and then the safety is no longer guaranteed) and without hot water or similar.
Who is bothered (like me) that the stuffing gets stuck at the pointed end of the eye and thus disturbs the filling or in the worst case the eyes are pressed outwards a little bit, can do the following: cut off with a wire cutter as far as shown in the picture below, in any case not too short, because otherwise the eye might not stay in place anymore.
But you really have to be more careful with acrylic than with cotton, acrylic melts away quite quickly. When the black part has melted a bit, blow out the flame (but it doesn't have to burn either, the plastic just has to become soft) and then press it flat with a small knife, spoon or similar, press it really flat. The black part then overlaps all around and secures the disc nearly unbreakable. This method is also very helpful if you attach the eyes to a separate "eye white", for example, as the pin of the eye usually disturbs when sewing and you have to insert it separately into the head.
Have fun attaching the safety eyes easily and without any pain in the future :o)