Frustrated by the inefficiency of leaker hose, we have, for the past three years, been relying on a homemade sprinkle irrigation system to keep our two raised bed veggie gardens going throughout the growing season. We'll be using the system again this year. A few basic tools and about 10 bucks for materials at the local hardware store will get you going.
No plans are needed. Take a look at ours and you'll have no trouble figuring things out.
Once you've got the rig assembled, find an old length of garden hose, chop off the male end and slip the stub over the entry tube. A 50-cent tightening hose clamp will provide a leakproof connection. There's a commercial version of this setup that will allow you to thread a stock =BE-inch hose connector directly onto their system. That sells for $24.95. Gardeners Supply Company markets something similar that is suitable for irrigating 3-by-3-foot raised beds, and that's selling for $16.95.