Measure, and mark the ground with spray paint the size your tilt up panel needs to be. Only mark the corners and do not worry about it being in square as you will attend to that when you build the form.
Measure, and cut enough 2x6 board to stand on end, and completely form a border around the area you marked for the panel. Stand the wood on its narrow edge, and join all the boards together, where ever there is a splice, and at the corners.
Square the form. Measure diagonally from one corner to the opposite one. Then do this on the crossing diagonal. You want the two measurements to match. Push your wood form from the corners out to change the dimensions. Check the measurement again, and when both diagonals are the same length go on to Step 4.
Starting at one corner drive a wooden stake, straight up and down, into the ground so the outside face of your wooden form is pressed against the stake. Do this every 4' all the way around the form. Drive the stakes in at least 6" and make sure that there is enough stake sticking out of the ground that is equal to the height of the form board.
Nail the stakes to the boards making sure to drive the nail head from the stake side and not from inside the form. An easy way to do this is to straddle the form, and press one foot against the inside of the form board while nailing the stake in place from the other. When all of your stakes are nailed in place, check the square of the form again. If your form has gone out of square, move the form, pulling up stakes as necessary, and resetting them until it is in square.
Build your rebar wall mat as designed in your site drawings. Your site drawings will specify the size ,and length of the bar, the spacing between bars ,and which bars must be laid down first (the horizontal or the vertical). Tie the bars where ever they cross with tie wire using a pair of pliers to make the tie. You will only need a snap tie where the wire is passed under the intersection, and then both ends are twisted together on top.
Lift your rebar wall mat, and support it with 2x2 concrete bricks every 3' or as otherwise specified in your plans. This will allow concrete to get under the mat to form the wall. If your plans call for a wall of double rebar mats, once the first is lifted and supported on your bricks, lay slab runners every 3' along the top bar of that mat and then build the second mat on top of the runners. Slab runners are 4' long metal "chairs" that are triangular in form, and joined together on what looks like sled runners. They are designed to separate and support mats and allow concrete to get between them.
Measure, and mark all openings and cut the steel with a saw to make room for the openings. Typical openings may be doors, windows, or mechanical openings.
Install any wooden "block-outs" required in these openings. A block-out is a mini-concrete form. For example, for a doorway you would cut an opening in the rebar wall and then use 2x6s to construct an inside form that will prevent concrete from filling that space.
Place your lifting, and locking plates into position. These plates are what will allow you to rig and lift the finished panel with a crane (lifting plate), and then connect the panels when they are standing (locking plates).
Pour your concrete as you would for any typical slab pour. When the concrete has cured, remove all of the wood forms from the concrete and it is ready to be rigged for lifting.