I can't tell you if you can do it yourself because I don't know your skill level. If the old and new dishwashers are similar and if the water supply and drain hose connections are similar and accessible, then replacement is usually easy. An experienced technician should be able to do it in an hour or less. It may take a homeowner a half day. If it's a complicated replacement installation, then it may take a technician a few hours and a homeowner all day. If this is the first dishwasher in the kitchen, things could get very complicated and new plumbing and electrical connections may be necessary.