Step 1:
The tube paper is 16x16 cm and the black paper is 8x8 cm. I taped transparent tape to both papers to make a glossy looking tube.
Prefold (or cut) the tube paper in half.

Step 6:
Press to the left by folding over the prefolded lines.

Step 5:
Repeat step 4 three more times

Step 2:
Prefold over these two lines

Step 4:
Fold over these two lines, use the prefolded line as guidance.
Tape / glue both edges together

Step 3:
Roll up, use tape or glue

Step 10:
Fold over these lines

Step 8:
Press flat, see arrow

Step 9:
Start with the left line

Step 7:
This is how to model looks now

Step 16:
Make a sharp folding line.

Step 15:
Fold the edge downwards on three more spots.

Step 12:
Prefold over the upper line and fold over the lower line. Use the upper part of the tube as guidance.

Step 11:
Done....

Step 14:
Fold the edge downwards on this spot, use the prefolded line as guidance.

Step 13:
Roll up around the tube, use tape or glue