Injector Making...

First obiously get Visual Studio with visual basic or c++ languages installed.

Learn Visual Basic Basic features or c++ basic features then you shall be ready for making the injector, just add a new windows form application, add listboxes, layers and buttons, and start coding as if you press a button window will open to choose the .dll then code for when choosed for it to appear in list box and in the layer as if injected correctly, the layer will show text "Injected"

Thats all I can say, the codes, well read e-books and learn yourself, or you would be leeching