I would have to start by saying that watering is by far the most difficult portion of growing a garden. During the summer its detrimental to miss even a single day of watering. This really puts a damper on any of those summer plans you may have for vacation. One thing I recommend setting up as soon as possible is an automated watering system. Depending on the size of your garden that could be just some spaghetti line or a PVC sprinkler set up. I take many trips and would not have a garden without some sort of watering system. All of my potted plants have gravity fed watering setups, my stationary garden has its own dedicated watering line connected to a timer.
There are many different types of watering systems, depending on the location and resources available.
Indoors I recommend using gravity fed systems,
Outdoors I would recommend using PVC and standard sprinklers if possible, for a less invasive set up you can use the standard spaghetti line