I do things like this when I remodel, so it's a bit of a skill I already have, so I would certainly take it on. I would suggest studying as has been suggested, and then undertaking the task yourself. If you get stuck, you can always call in a pro.
For power you can either hard-wire it to a box or attach a "pigtail" or plug-in for an existing outlet like the one under the sink you might have for a garbage disposal. For water supply, you can either replace your angle stop with one that has two outlets, or add a tee. Then a plastic of braided ss covered hose to the washer. For the drain, the dishwasher will probably come with a hose, and you replace sink drain with one that has a tee in it for this purpose.
Drill/cut a 1-3/8" hole in the sink cabinet wall between the d/w and the sink to pass the supply, drain and power through. Be sure to check for leaks before installing the bottom front cover on the d/w.
Also, follow the installation instructions for the d/w and pay attention to the details like making sure to screw the front to the cabinet or countertop to prevent the appliance from tipping forward if both the upper and lower racks are loaded and out.