Here is a blanket that you can make using your leftover yarns to add some color to your boring couch. This is a beginner friendly pattern with links for video/photo instruction

Materials
Various skeins of fingering weight yarn. Suggested yarns: Good Ole Sock, Simple Sock, Silky Sock held double throughout
US size 7(4.5mm) double pointed needles
US size 7 (4.5 mm) 24 inch circular needle
Tapestry needle
Lengths of waste yarn
Crochet hook to match needle size
Locking Stitch marker

Size: Measurements
Finished measurements
57x36 inches or size of your choice

Gauge
Gauge not important