Building a fixed irrigation system (watering) for you plants, flowers and lawn requires a bit of planning. You will need to lay polytube around your garden fixed to a water supply and then you will need to attach sprinklers or other devices to water your beds and plants. The attached nozzle type will depend if you wanted to spray, drip or soak your chosen area.
The first thing to check is the water pressure of your property, which basically means checking how much water your water supply produces over time. The more water means higher the pressure but this could also mean you flood your areas rather than give them the correct amount of water. Thankfully you can now buy battery powered flow controllers that you fix to the water source and you can control the time and the flow rate of your system. You are basically creating an automated drip irrigation system or micro irrigation.
Irrigation kits are available to buy online or from a garden centre. You can also buy individual components depending on your needs.
Sizing up and laying the pipework for your irrigation system is easier if you are experienced and knowledgable about plants. If you are worried about the cost and you don't think you are capable of laying the system you could buy the materials and get your local gardener to lay the irrigation system. You could plan it together and then he could implement your design.