Well I'm a 4a texlaxed head and I blow dry my hair straight using a ceramic blow dryer (from Sally's) with a comb attachment. The key for me is to detangle my hair before blow drying.
I put Loreal Blow Straight on my hair first along with a Leave In Conditioner. I blow dry my hair if four sections starting at the top left, top right, back left, back right. I've found that if you blow dry the top of your hair first you can cut your blow dry time in half. For silky shaky hair, the less amount of product the better.
Then I usually use a serum for flat ironing and I get straight bouncy hair.
The key for me is to blow dry with care, distributing the heat down the hair shaft and blow dry your hair into the style you're going to flat iron it into. So blow down the hair shaft for shinier, sleeker hair.