If your're asking how to do this on SPSS, you go to Analyze, General Linear Model, Multivariate. Bring over your Dependent Variables and your Iv's. Go to options, bring over all Factor and Factor interactions to the "Display Means For" , then click compare main effects and keep on LSD. Then run your test. Now analyzing it can be tricky and it's not something that I have the patience to type out online (it can become quite lengthy, depending on your variables). Hoped this is what you are looking for.