I have natural 4b hair that I would like to straighten to do a length check after not using heat since May 2009. I have shoulder length hair that is medium in thickness and have been wearing twists for 7 months. I am not very skilled at doing my hair but I am trying to learn and get better at it so I won't have to rely on hairdressers since I have had bad experiences with them. Should I use a comb attachment to blow dry it then flatiron it. I don't need it bone straight just straight enough to show the length.