I haven't worked extensively with velvet itself, but a few things I can mention from working with similar materials...
Velvet is a plush material, meaning it has pile - think of it like a rug or a carpet. The fibers that stick out from the weave of the material itself. This means it also has nap, which refers to the direction the fibers lay in. If you run your hand across the material in a few different directions, you'll find that the fibers will naturally lie one direction and look smooth and glossy. If you run your hand the other direction, the fibers will stand up and show a rougher texture, with a less glossy finish/darker apparent color.
When you make your garment, make sure that your nap is all running the same direction. If you're using a commercial pattern, it will have an arrow on it indicating the grainline of the material. Make sure you line this up with the fabric grain correctly, and make sure all your pattern pieces face the same way (e.g. neckline vs waistline) so that you don't have fabric pieces with naps running different directions.
Also, those plushy pile fibers will begin to flake off the edges of the material once it is cut. These can end up down in your bobbin casing while sewing and clog the mechanism, which will make your bobbin thread catch and knot up, potentially causing holes, picks, or pulls in your fabric - which, at the price of velvet, does not a happy sewer make. Keep in mind that you should clean out the bobbin casing more frequently when you're working with velvet or other plush fabrics to prevent this from happening.
Be careful when ironing. I don't know the fiber content of the velvet you are using, but synthetic fibers are in general more sensitive to heat than natural fibers like linen, wool, and cotton. If your iron setting is too hot or you hold the iron in one place too long, you can burnish or scorch the material, and you'll end up with a big iron mark in the middle of your fabric. Iron on the inside of the material as much as you can to prevent this, and test out different iron settings on some scrap pieces a few times to figure out the heat tolerance of your velvet.
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