I use AutoCAD for design, but I suspect that the features and processes are similar. First, I create the wing plan form. Second, I layout the rib locations. Third, I dimension the chord length for each rib. Now comes the fun part.
I go to some airfoil data source like http://airfoiltools.com/
and select an airfoil. There are other sites that are just as good, but I find this one fairly easy to get around in. Once you have selected an airfoil, you can download the .dat file for its coordinates. Draw a p-line using these coordinates and then smooth the lines. You will wind up with a rib of your choice with a chord length of one (1). Then all you have to do is to 'insert' the rib into your drawing using the measured chord length as the 'scale' for the 'insert'.
If you like, I'll be glad to make one for you. Just sent me a PM.