The plan for this is attached. Cut out the parts and fold it up. Take your paper shade and sit it down so it is stacked. Raise the long sides up and together, so that the pleats make a rounded top if looked at from the narrow end. Decide how many pleats you want to have in this top section. I chose 7, which is the same number of pleats as I allowed for each scissor "cell", and this gives a good enough shape. Too many will mean you might run out of shade for the rest of the lamp, too few will mean you get a pointed tent shape instead of a nice round shape.
If you have wisely decided not to make the hangers (section below), then you only need two cardboard stringers for the very top of the shade, just to keep the shape of the rounded part. Cut two sticks of board 240mm long and stick their ends into the pleats where you have decided to end the top. These stringers simply sit on the little platform that extends out the bottom of the handle. Glue them if you feel confident, I added a bit of stick-on velcro so I could adjust this wayward shade. Do a test fit - Gather up the shade, and peg it, bunched up if you can, then take it to your top-most bamboo skewer on the lamp frame and clip the tabs that hang out the bottom of the handle on. Hopefully it will balance. If not, don't worry too much, it'll have a tendency to right itself once the shade is down. So take the shade down carefully, checking it isn't caught on the ends of any of your skewers.
These stringers are optional. My original lamp didn't need them but this one is a little bit more wayward (twisty), so benefitted from them. I think they might be a worthwhile addition to a standard configuration, though a lighter type of board would be preferable. They also make it a lot harder to deform the shade by accident.
Essentially, I fitted a set of cardboard stringers (240mm long) into the pleats of the shade (see the pictures) at regular intervals, glued at the ends, holding the long sides of the shade together. The main thing this does is keep the lamp a bit squarer. I used five sets of stringers (that includes the very top ones, which are not optional, I think), each set 7 pleats apart.
Slight digression - showing my working-out:
I planned to have the stringers resting on hangers which were themselves hanging on the central pivot skewer at the top and bottom of each shade. I made all this up (pictures attached), and this had the great benefit of spreading the weight of the shade over the whole structure, preventing the shade from sagging - where the top pleats are stretched out, and the rest of the pleats are gathered up round the bottom.
What it also meant was that instead of having a nice even progression of pleat size, from big ones at the top, to slightly smaller ones at the bottom, the look was a lot more higgledy-piggledy - overall less even, less easy on the eye. So I took the hangers out. I was never comfortable with that extra complexity anyway.
If you decide you'd like shade hangers:
Cut 10 strips of cardboard 15mm wide, and fold pairs of these and glue them into rectangles 95 x 390mm. Cut a notch at the half-way point and balance one each on the central set of bamboo skewers. The cardboard stringers you added to your shade will rest on these hangers. Add a raised tab at the end of each hanger to stop the stringer from slipping off when the hanger is tilted.
Now that the shade is on, the lamp has no firm bits with which to pick it up, and that's just the most practical reason why we need to add some extra parts to the base. The other reason is that it looks slightly bizarre with just it's dainty ankles hanging out from under it's voluminous petticoats. Personally, I think it looks hilarious. Have you ever laughed a lamp? I have. It certainly lightened my mood! ... Sorry.
This is just a set of four panels which lock together around the existing base. Some strips of card with tabs on them (shade edge - pdf plan attached) are glued to the bottom edge of the shade and these slot into the side panels on the base and keep the bottom edge of the shade under control.
And, all of a sudden.. That's it finished!