When I was a kid, my grandpa had a beautiful, green garden. As much as I can recall, I don’t remember him watering, not once ! No sprinkler system, no soaking hose, nothing. I rained enough that he didn’t need to do anything about water.
So when I started growing food in Utah, I didn’t really pay much attention to an irrigation system. I watered with a regular hose sprayer for 20-30 minutes per day… for the WHOLE GARDEN ! We assumed, wrongly, that if the dirt on top is wet, it’s good enough. Big, big mistake ! If you live in an area where people have sprinklers for their lawn, you probably need an irrigation system. If you already have sprinklers, good for you, you are good to go. But if you don’t, don’t panic; it will not ruin you.
We could not decide if we wanted a soaking hose or an oscillator water sprinkler. We went for both. We live in the middle of a desert, so we do water a lot. One hour before the sun gets up, and an hour when it gets down, for the entire garden/lawn.
We have friends who tried to be savvy on their water consumption this year, and we did that for the first two years. The best advice I have for you is to try it for yourself. If you start small, it will not cost you a fortune in material. I strongly recommend a timer, it is so easy to forget to water.
Good luck !