If you are really just worried about the top then before you roll the sections tease the hair with the small end of the comb. The correct way to backcomb your hair can be seen here
http://www.youtube.com/watch?v=raBESnDG0PA
I see lots of girls that backcomb incorrectly and it doesn't stay... this is how I do mine and about 1/2 the girls at works hair too... it looks silly before you smooth it but it will stay for days.
If you have extensions I wouldn't use a ton of product... since youre more worried about the top staying than the curl at the bottom you really need the teasing more than product.
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