From (fixed sender address)
Set your sender address
Fill this in once. It will be printed as the "From" address on every label.
Add a customer
Round label (50 mm)
Upload your round-label image once. It is saved online, so it is there on every device and nobody has to upload it again.
No image yet
Sticker roll settings (set once, saved on this computer)
Width = width of the whole roll backing. Height = distance from the top of one sticker to the top of the next. Use the same two numbers as the paper size in the printer settings and in the print window, then hold the printer's Feed button to calibrate.