I can help you more if you tell me what is happening wrong to your dough or pizza? If you could also provide the recipe you use along with the mixing procedure/time, would be even better.
With regards to the steps you provided, I think there could be some potential mistakes.
First of all, I don't see you mentioning the hydrating of ADY. In order for you to use ADY, you need to hydrate it with about 1/4 cup (taken from the recipe's amount of water) of warm water (105 F) and let it activate for 10 minutes. By that time, it should be foamy and have a nice yeasty smell. If this doesn't happen, it means your ADY has gone bad and you need a new one. You should also start by putting the recipe's amount of water in the mixer's bowl, completely dissolve the salt and sugar together. You can then add the oil, some of the flour and mix until your dough is still very wet like a batter where then you add your hydrated/activated ADY. Mix for a minute and then add the rest of the flour and continue your kneading procedure.
I hope that helped.