We all don't have "barns" where we can suspend the boat from the ceiling, and have to work out of doors. I don't have photos, but have used hydraulic jacks to do the lifting, with blocking between the jacks and hull. Some use cement blocks. I have seen these crack under load--and would not recommend them. I use only wooden cribbing--made either of land scape timbers or 4 x 4 and 6 x 6 to take the weight of the boat on the keel. I used jack stands for the stern to balance the boat.
What sequence you use to block the boat off the trailer, depends on the bunks and trailer frame. I will try and move the trailer forward at least a couple of feet on the first lift. That allows good blocking at the stern for the keel and both sides of the transom. Then one jack forward with good cribbing is all that is necessary to walk the trailer out. I prefer to have 3 points of weight distribution the keel, when you will be working under--and a second set of jack stands about at the helm area with minimal weight--but as a safety. Be sure and chain the jack stands to each other to keep them from sliding out.
I build my cribbing up 2 pieces fore and aft, then 2 athwartships. Not just stacking one on the other--unless you are fortunate to have a 15" x 15" piece of timber.
Safety is key. Jody shows the full face mask which is very good. You must have eye protection. When I used to do this, i used a full Tyvek suit with a hood, and nitrile gloves--tape around the cuffs. etc. Home depot has them for $15, Amazon; $12 and Harbor Freight $8. I prefer the cheaper disposable ones, but for some applications I would use a more expensive suit--such as building a boat--where you wear it daily for months at a time. Many professionals use a positive pressure suit/breathing apparatus, but with a good mask and in the open, it is OK for painting a bottom one off with just a good mask and filtration.
