If you want to teach PPL's what entry into IMC is like get them to wear foggles when facing out to sea on a grey day, that's the closest they'll get beyond actually going into cloud.
Removes the visual references and they may then appreciate how bad it can be.
Also the training relating to "if you inadvertantly enter cloud turn 180..." is far from how most people will end up in this state.
For my sins, I've been in solid cloud at an unusual attitude and it's not fun, I was flying fast between cloud on top and fog below and decided to grab a map from the back, in the short time it took to root around and find the right map in the bag and with no peripheral vision I went from straight and level at 120kt to decreasing airspeed, almost 1000ft/min climb, pitched over at least 20 degrees and in solid cloud. Not fun, with all the best will in the world it took a lot not to panic and to rely on the instruments and not the feeling in the pants. The final outcome probably dictated more by luck than skill or judgement.
I'll put that one in the accumulated luck bag........