Drying/Preserving Flowers; Advice Needed

I want to dry/preserve some sweet annie to use in my crafting. I've done an internet search and have decided to use the glycerin method of preserving it; I've discovered that when it's air dried it tends to shatter and shed. My question is about the glycerin. I've found different kinds (at least, I assume they're different), most say they're used for soap making. Has anyone used the glycerin method before, and do I need to purchase a particular form of glycerin for flowers?

Just giving this post a little bump before it gets lost. Still looking for advice.

the only way I have ever preserved them was coated them thickly in hair spray and hung them upside down in the closet for around 2 weeks. Seemed to work

I thought of that, but hadn't tried it yet. Thanks for letting me know you've tried it and it worked.