Retractable Clothes Line

I tighten the plastic screw in a wooden fence outside ... then tighten the screws in the metal ... but do I use metal screws to make the hole for the little plastic ... and then bang the bit of plastic, then go back and screw in metal or plastic?? or do I start a hole, then carefully tighten the plastic bit in. .. and then the metal screws in this situation??

The plastic screws "are anchors to be used on products such as drywall. The metal screws can and should be used only for screwing in the wood.