shake it
I learn hip movement and exercises for body movement (including shoulders) from Cuban guy (from some Dance Art University in Cuba or something).
I had been dancing for 4 years (Gringo style

) and I slowly started getting hips and body movement the way Cuban moves and I said right away “Wow! So this is Salsa”. It changed everything for me.
I concluded, with exercises or not, you have to get you hips moving. Everything comes from hips. I don’t think guys are shy; it is more that no one knows to explain. Figure #8 is I think the worst explanation and doesn’t help. But looks like you are there to get hip movement or at least close. Once you get that, the shoulders and body will follow. I wish I could show you.
You can do exercise to force you shoulders to move. Dance only you shoulders in Salsa rhythm (no footwork, and in the beginning no hips) by lifting them. This is just to get use to the feel. When you want to include hips and footwork stop thinking about shoulders, they will move for sure (if you have hip action). Although I have some exercises for the rib cage I think just concentration on shoulders will work too. Note: it is important to stop thinking is it left up or right, relax and dance.
For shimmes, I learn it is the best (if you have problem to do it) is to try exercise sitting on a chair (because hips should be independent of shoulders) and than shake it (should be relaxed). Some peple have problem relaxing the shoulders and not moving all body. Also girls are shy. There is a topic about Smiles, girls, try this with stone-faced guy and see what happens

.
Some styles don’t require so much body movement and some argue about it. I think it won’t spoil any style you know/dance. Altough I do it much less in N. Amer. styles (I can not do a lot of spins myself and dip partner and on the top have hip/shoulder movement in the same time).