You don't post images - you post links to your own web page that has the image you want to show. So figure out how to get a web page for your image from your internet provider.
I made a couple very plain foccacias this past week. Both were super similar treatments, but the second one got a HEAVY does of olive oil on the top. Rubbed all over generously. It browned LOTS. The bubbly spots got a little black. The unoiled one didn't brown nearly so much.
Still, what temperature are you using? I used 550 degrees pre-heat, then down to 475. Pretty darn hot.
I also happened to use extremely wet dough. Can get it off your hands, but it's hard. Need oil.... I hadn't intended to make foccacia, was just experimenting, but it was so wet I couldn't really shape it, so what the heck. And oh was it good.
My methods/recipes came from "The Bread Baker's Apprentice" by Peter Reinhart. It's an excellent book, lots of sound advice on bread baking.
Nancy