Add the campden 24 hours before you plan on pitching yeast. I would add them as soon as you get the juice home.
Currently I am on week 2 of my cider, I raised the gravity a bit but mine is still fermenting. I added some yeast nutrient for mine, but if you aren't added anything you probably won't need it.
I would say at least 4 weeks in primary. Then to clear it rack it to a secondary. Then you can age it in the secondary or bottle it and age it. Either still or prime it to carbonate.
One of the biggest challenges with cider is getting it to clear. Especially with fresh juice.
I'll give you a basic run down as I see how to make cider from fresh unpasteurized juice.
1.) Get Cider
2.) Drop in crushed campden tablets, 1 per gallon.
2.5) might be a good idea to add any sugar you wanted to boost gravity with before campden. If you add sugar, good idea to add yeast nutrient as well, and make a starter if you are impatient.
3.) wait a minimum of 24 hours
4.) Pitch yeast
5.) wait about 3 to 4 weeks or until fermentation slows or stops, check gravity 3 days in a row
6.) rack to secondary for aging and clearing. Add any flavoring/spices now
7.) wait however long you want to age, some like it young, some like it 6months to a year later.
8.) Bottle or Prime and Bottle.
9.) Enjoy the fruits of your labors.
For a starter, I just used 100% apple juice, and I stepped up a White Labs English Cider vial to about 200ml of yeast for my two gallon batches, but my gravities were around 1.064(draft) and 1.088(still)