Lactic acid in legs after a run

A day after a long run, my lower body often feels fried. Hard to walk. Could you advise on the best stretching routines, roller types, or techniques to alleviate this? Additionally, I'm curious about the effectiveness of massage guns for recovery.

Currently, I'm trying the method of elevating my legs against a wall to reduce lactic acid buildup and prevent stiffness the following day. Any guidance on these recovery strategies would be greatly appreciated!