Welcome to the board. With FMQ you have the quilt sandwiched together, pins or special spray glue or elmers school glue. Then mark with any tool, chalk, frixion pen etc which can be removed after quilting. then try to keep on the lines. Your stitch length is slightly larger as well. Thread can blend in or show clearly. Pair of gloves to help with holding and manoeuvring the quilt. Patience and time required to master this beautiful technique.
Try on sample pieces to get it flowing freely. Relax.