Remove the tension on the old blade using the knob on the top.
Loosen the screws holding the blade in place on both the top and the bottom (adjusted from the right hand side). I used a 5/32“ hex wrench, which worked but was a bit loose. It probably takes a metric size if you can find them, maybe a 4mm? (If you figure out which size, please add it to the wiki?)
Remove the old blade if you're replacing it.
Hook the blade pins into the bottom blade holder. The teeth on the blade should point down, pushing the wood into/against the table when cutting (not lifting it up). To access the bottom part, it helps to tilt the table to the side.
Holding the blade with the bottom pins still in place, hook the top pins in place. It will probably help to adjust the tensioning knob to catch the top pins and hold the blade in place (but not too tight yet).
Tighten down the top and bottom screws holding the blade in place.
Adjust the tension knob. You want the blade nice and tight. It should give a nice “twang” when you pluck it.
Adjust the table back to square (or whichever angle you like), and check it with a tri or combination square if it's important to you.