Your questions require a book's worth of answers, which is probably why the regular experts have not touched this one. I'm no expert, but will try to get you on your way.
Question: Should I prune? When and how"
Answer: Too many unknown variables to give precise answers. I would recommend pinching the tip growth when the new wood has five or six leaf nodes.
Question: How do I know when the fig is ripe?
Answer: All of the varieties I have go through a sort of metamorphosis (ok, so I can't spell). Just before the fruit become ripe they swell up dramatically, turn color, get soft, and droop, all within a couple of days.
Question: Lots of water, or not too much?
Answer: Fig roots do not like to be wet; the amouint of water depends upon the texture of your soil, and its ability to hold moisture while still allowing airspaces. DON'T DROWN YOUR PLANT!!!
Question: Fertilizer?
Answer: Everyone has their personal favorite, but for container-grown plants you can't go wrong with a slow release like Osmocote, used as per instructions.

Novita,
There are no requirements in regard to pruning. It done most often to meet the needs of the space, not to encourage fruiting. Although Herman from NJ pinches the growing tips to encourage ripening of fruit already developed. You might want to do a search of the forum archives to see exactly what he recommends.

For long term potted figs you do want to fertilize. I used to use a weakened solution of MG once a week during watering. When I refreshed the soil I'd add time released fert. and/or a handful of bloodmeal and cut back on the MG. Nowadays most of my figs in pots are merely waiting to be put into the ground, so fert. isn't so important since their fresh potting medium is sufficient.

As you live in the PNW your figs may be suffering from a lack of heat. From what I've read in books and garden posts, only select varieties will do well in your area in regards to fruiting. You may want to take a look at Kiwi Bob's page for some ideas for good varieties. You might also try prositioning your fig pot against a hot, sunny brick wall

Here is a link that might be useful: Kiwi Bob

Thanks so much for attemtping to answer my big questions! Next time in the library I am going to look for a fig book. Also, Maybe I need to buy a named variety good for this area like Desert King. I am learning, and intend to harvest a crop eventually! Thanks again.

Desert King is an excellent choice. I have 2 Negronne trees and both breba & main crop, especially the main crop seems to confirm its prolific status. I have no idea how good it taste but readings suggest its great. I have Peter's Honey & they seem to be productive too. I got my plants in Abbotsford & Chilliwack.