I am trying to do the sheetmetal tutorial and i am stuck

I am using sp4.0 of solidworks premium. I am trying tocomplete the sheetmetal tutorial step SIX of the creating an edgeflange portion. I am supposed to click on smart dimension and thendimension the edge flange tab. Usually with smart dimension I canroughly dimension the lenthly and then click on a pop up box andtype in the value I want. In this case 36mm for the notches on eachend. I am unable to do this at all. Could someone tell me what I amdoing wrong step by step as I am a novice. I tried to upload mypicture but the webisite says it is not a valid file type?SolidworksSheet Metal