Epson TM-300A Operator's Manual page 19

Turn on the printer.
While leaving some slack in the roll paper, insert the end of the roll paper
straight into the paper inlet. The printer automatically feeds the roll paper into
the printer.
Press the FEED switch to continue feeding the paper until it extends about
20 cm beyond tear-off edge.
Remove the take-up spool from the take-up frame.
Remove the side of the spool and insert the end of the paper roll (journal paper
when using 2-ply paper and 3-ply paper) into the groove on the spool and wrap
the roll paper around the spool two or three times. Install the flange to flange
shaft.
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