In June, you'll be cutting off 'excess growth' - long vines without grapes (the grapes tend to sit close to the stem).
Next winter, this is what I'm doing:
The red lines give you an idea of what to keep and what to loose. Just establish a pattern in your head and trim away the extra branches.
The green bits show a dilemma situation. On the right side, you could go with the upper or the lower branch, but since the upper branch seems to grow in all kinds of weird directions, I'd prune that one and keep the lower branch.
On the right side I've circled the area of a similar kind of dilemma area. You are the gardener, you decide where the grape vine goes and grows.
When cutting of 'extra growth' in the winter, KEEP TWO TO THREE BUDS per branch. So where I've drawn the red line, between the stem and the cut should be two to three buds/eyes (where new growth starts in the next season) per stump.
In the beginning I always kept three, now two. Leave maybe 3/4 of inch branch after the second or third bud and the cut. Because frostbite might kill of the tip of the branch, and this way you're saving the bud.
I hope this is somewhat clear? If not, just ask. And whenever in doubt, STOP and take a break. With a mug of your hot beverage of choice in hand, stand at some distance of your work and look at it. What does the vine want ? What do you want? What are the cuts you'll be making?
Good luck!
