50 mm bleeds are to big, my software cannot do bleeds that big?
If you want to work with bleeds, its easiest to do the material in 1:10 (10%) size with 5 mm bleeds.
There is no need for cutmarks.
Do i need to make the print file as wide as the fabric?
The repeatable file is only needed.
Deliver possible side texts as a separate file. The resolution should be 150-200 dpi in 1:1 (100%) size.
Make the repeatable file always in its final size. There can be no bleeds, frames or anything that should be wisible on the ready made fabric.
What size of text is readable in a 3 meter wide banner?
A rule of fist is that the size of the text needs to be half of the wieving distance. for example a banner seen from 10 meters away should have text atleast 5 cm high.