You can buy a kit with all you need to fit an outdoor tap from all the major hardware suppliers. There are slightly different kits for copper and plastic pipes but they both work on the same principal. Here’s what you do to install it
Firstly you need to attach the saddle clamp to a suitable, cleaned cold water supply pipe. Then screw the self-cutting tap into the saddle clamp.
Next, put the rubber washer in and connect the hose to the tap. Check for pipes and cables, then drill a hole through the wall at a slight downwards angle towards the outside. Use a hammer action drill with 16mm masonry bit to do this.
You can then run your hose through the hole. Mark out suitable fixing positions for the tap, then drill the holes and fix them to the wall using the wall plugs and screws provided. Finish the job off by pushing the supply hose onto the tap stem and tightening the hose clip with a screwdriver.