I'll take a general stab at your questions, although you might be a little more specific in the future to avoid confusion.
step 1: rent/borrow/ get a boat to suit your budget
step 2: learn to sail via formal lessons, or crewing for others, or just find a friendly sailor
step 3: go sailling
there are not yet any hard and fast rules for this hobby/sport yet, although a boating course will help you to be safe and a little more aware and confident on the water, It will also make you aware of the equipment you should carry onboard.
to sail, i recommend not being prone to seasickness, and to be healthy enough that you can climb around the deck with one hand free. If you are looking at sailing a dinghy, definitely be healthy enough to swim and/or tread water.
Honestly, try it out before you jump into sailing. you may or may not like it. It's not for everyone, but you may find it quite enjoyable and satisfying.
1. Check status of the boat:
1a. Is it on land or in the water?
1a-i. If on land, put boat in the water.
1a-ii. If in the water, is the water staying on the outside of the boat? (If not, stop water from coming in.)
2. Untie any lines (ropes) connecting boat to land/dock/tree etc.
3. Open cold beverage of choice.
4. Raise sails.
5. Wish you had a bigger/faster/prettier boat.
6. Reverse steps 1-4 and return to daily grind.
Check out the webb for local coast guard flotilla's that give both basic boating and sometimes sailing lesson's. Although we've been sailing for a while, my wife & I went to the basic ABC class and there were a couple of items that we hadn't thought of. Also, see if there's a marina close that gives lesson's. Start out small, say 18ft without a motor, so you'll get the feeling of how the sails will work for you and the boat.