I have spent one week on the island every August for the last 18 years. We stay in Oak Bluffs near Ocean Park (where the gazebo is across from the beach). My favorite way to see the island is on bicycle. You didn’t say whether or not you will be biking. You can bring your bikes on the ferry (a small additional fee) or rent on-island. If you take a ferry that drops you off in Vineyard Haven first, you can explore VH and then Bike to Oak Bluffs (about a 15 minute ride, depending on your fitness level). The two towns are distinctly different, so you should really try to see both. If you get to the island early enough, have breakfast at the Black Dog Tavern in VH when you get off the ferry. All tourists must eat there at least once in their lifetime, and breakfast is more affordable than dinner. There is also a separate BD bakery for coffee and something light if you are more inclined to not spend the time eating. Be sure to walk the Main Street to get a feel for the types of businesses here. The bike ride to OB takes you along the water, and the approach in to OB and the Harbor area is very picturesque. In OB, be sure to check out the Methodist Campground/Tabernacle area (Gingerbread cottages)for photo ops which is not far from OB harbor. Park the bikes and walk the Circuit Ave area, (which is very touristy) and you will get a very different feel from VH. Take a ride on The Flying Horses Carousel (yes, ALL ages ride it and be sure to get an outside horse and if you get the brass ring you will get a free ride). From OB, you can then travel past Ocean Park and State Beach and eventually (30 minutes) make it to Edgartown Center. I find Edgartown the most picturesque in a quintessential New England way. It is far more upscale than OB and more lively than VH. (VH is a dry town.) When you get to Edgartown, this is a good place to pick a watering hole down by the harbor and have a nice frozen drink and appetizer. If biking, you can return to OB at the end of the day instead of VH to take a ferry home (depending on ferry line taken and schedule). There are lots of amazing places on the Vineyard, but if this is your first trip and you only have a day, I would focus on getting to the 3 towns mentioned to get a feel for the differences. Lots of “day trippers” take the ferry in to OB and then get a very skewed view of the Vineyard, (and never go back), so you owe it to yourself to explore the other towns. A day will give you ample time, and if you take the Vineyard Transit bus in stead of biking, you can easily cover these towns at a leisurely pace, with time to stop at the beach for maybe an hour or so before getting an ice cream at Ben and Bill’s on Circuit Ave or some fried clams at Giordano’s takeout and then catching the ferry back to the mainland from OB. The VTA offers a day pass that will allow you unlimited use, but even the separate fares were very reasonable last time I used the bus. You can also rent mopeds (fairly dangerous since they have to ride with auto traffic) or an automobile (reservations required in advance and very $$$). If you have specific questions please feel free..