The following is based on extensive research by myself, Varen and others. It deals purely with the process of turning your vine cuttings into grapes. How you go about producing different flavours to boost winetasting skill is a whole other (currently unknown) world.
With this information, and a little bit of care and planning, anyone should be able to grow any number of grapes with any desired concentration. The next step is to grow large numbers of similarly grown grapes and experiment with fermentation times to work out how to best bring out the flavour of your wine.
If any of this is unclear, I'm happy to post more details of my research, data, charts etc. I was aiming to do this today, but ran out of time and felt it was more important to get the basic info out.
Some general hints:
antichaos's howto is a great writeup, but is also old and some of the information is inaccurate as a result, so here are a few corrections:
Aside from those minor points, this is largely correct and a great guide for going from cutting to grapes. However, you still might not be sure on what you should be doing to optimize the usefulness of your grapes. There are basically four reasons to make wine: Winetasting, Distillation, the Festival of Ra, and the Feast for the Senses.
Growing grapes for winetasting requires the least amount of thought, as any grapes will do. You don't need to leave them on the vine, you don't need to get concentration up. The only thing you need to worry about getting is grapes.
For distillation, what vinetype you use depends on what spirits you want. If you wish to be able to produce a wide variety of spirits, you will want to choose a vinetype that has good tannin production in order to get the higher spirits such as Vegetable, Mineral, and Fish. However, if you just need spirits for Alchemy (which needs only Grain Spirits), then you can use a vinetype with slower tannin but higher residual sugar per day or faster alcohol. For high tannin production, you should choose Black Globe. It doesn't have the fastest alcohol conversion, but it's far from the slowest. If tannin is less of a concern, Honeydrop is probably your best bet as it will convert residual sugar to alcohol faster than any other vinetype.
The one other thing to keep in mind when growing grapes for distillation is that you need to leave your vines up long enough to accumulate residual sugar to convert to alcohol. If you want 12 alcohol wine, you'll need a minimum of 12 residual sugar. Most vinetypes accumulate 2 residual sugar per day.
Grapes for Ra festivals are similar to those for distillation since you're thinking primarily of high alcohol as a result. However, Ra wines need to be 2 vintages old. That means if you ferment your Honeydrop grapes and get 10 alcohol in 3 days, you still can't use it for Ra for another 10 days at least. This is why Sugar Skin isn't a bad choice for Ra wines (if you're going to use a stock vine). You want to get Ra grapes off the vine as quickly as possible while still accumulating 10 residual sugar so they'll have an older vintage than regular vines, which would need to be up for twice as long and might stretch into a newer vintage. Since once you take the grapes down you still have to wait at least 10 days before any wines made from them can be used for the Ra festival, Sugar Skin's slow alcohol conversion doesn't hurt anything, since it'll definitely be at 10 alc by the time you can actually use the wines. It should be noted, however, that Honey Drop accumulates Residual Sugar at the same rate that Sugar Skin does, so there's no reason not to take advantage of Honey Drop's fast fermentation rate.
These grapes require the most attention by far. Grapes for making banquet wines should have a minimum of 700 concentration and 30 residual sugar. Moreover, they should be good tannin producers, which means that Sugar Skin should definitely be avoided. Black Globe is your best bet here for stock cuttings since it has the highest tannin production of any stock vinetype. It would not be a bad idea to look at getting some good crossbred vine cuttings either, as some of these have better residual sugar production and tannin production than the stock vines. Since you're spending so long on getting the concentration and residual sugar up, you should make sure you get enough grapes per vine to make it worth your while. I would say that you want at the very least 1500 grapes per vine. If you're growing on very few vineyards, you should get even more per vine. You want at least 25000 grapes total, and 100k and up would really be preferable.
I won't go into detail about the winemaking aspects of these at this time, as they're somewhat complicated and require a lot of explanation.