Help with setting up sump

[impreza]

I have a tank with an external overflow with a 1.5" bulkhead and a 1" bulkhead for a return in the back of the tank. I have a sump that is ready to be used and I am about to buy a MAG submersible pump. Now, what do i need to buy to setup all this up? Where do I purchase the materials? I am completely new to sumps! I am planning to use spa flex, where is it available? I want something super simple for my setup. I am planning on having the overflow drain to my sump and have the water return to the tank, nothing fancy. I just want to make sure I get all the materials needed. Another question I have is how do I attach the spa flex to the return and overflow? Do I use clamps or..??

Thanks