You bought an embroidery design, but it came as a DST, JEF or EXP file and your Brother machine reads PES. CutArc Embroidery (Beta) converts it in your browser on the free plan. The file never leaves your computer. You need a free CutArc account.
Open the file
In the studio, choose Stitch file in the Add panel, then Choose an embroidery file. The summary shows the stitch count, size and colors. Note the stitch count; you will use it to check the result.
The same steps work for VP3 and XXX files, and in reverse: you can save a PES as DST for another machine.
Open it as a design
Choose Open as new design. The stitches load as they are in the file, on a canvas of their own.
Choose thread colors
DST files carry no color information, so you may want to pick real threads from a catalog for each color step. This changes colors only, never stitches.
Save as PES
Choose Export, pick PES, then Download file. In Chrome or Edge you can save straight to a USB stick instead.
Check the result
Open the new PES with Stitch file again. The stitch count should match the file you bought, or be a few stitches higher: PES adds a small tie-in stitch after some jumps. The design itself does not change.
What stays the same
The stitch layout and the size stay as the designer made them; PES only adds the occasional tie-in stitch after a jump. Bought stitch files keep their original size in CutArc, because resizing a finished stitch file changes its density and can spoil how it sews. If a design is too big for your hoop, ask the designer for a smaller version.
The PE-770's hoop is 5×7 in (130 × 180 mm), so check the size in the summary against your hoop. We have sewn test designs on a PE-770 and a PR1050X; the other formats are written to their published specs. As always, sew a test on scrap fabric with the right stabilizer before the real piece.