After a long run, the best way to recover is to stretch. Focus on your lower body first, this includes stretching glutes, calves, hamstrings and quads as they take a huge brunt of the impact and tend to get tight first. Once these are well stretched focus on thoracic extension as we tend to hunch toward the latter end of long runs.
Here are a few stretches that I like doing post run:
Glutes: Pidgeon pose. Have the front leg parallel with your torso for a deeper stretch. This can also be done on an elevated surface (ie. bed, chair, bench, etc.). If you want a deeper stretch hug the bent knee, this will help stretch out the piriformis muscle and you will feel it along the side of your body. If you want an even deeper stretch, on an elevated surface, once in the position, either yourself or have someone use a percussion massager on the tight parts of your glute. Hold for a minute or two and then swap to the other side. Do this 3x, trying to get deeper each time.
Calves: Calf raises on an elevated surface (curb, step, etc.). Hold the wall or something to help keep balance. Tip toe (plantar flex) and then slowly lower your heel until it goes below your toes (dorsiflexion) and repeat. 10x per side is one set and do this 3x. Additionally, the wall push helps stretch the calves as well. Pretend you are pushing a wall with both hands while having your legs being in an almost full lunge position. Push the wall while trying to bring down your rear heel. If you can reach the floor with your heel easily, bring your foot back further. Hold for 10 seconds then switch and repeat.
Hamstrings: With your legs about shoulder width apart, bend forward at your hips while keeping your legs as slightly bent. You should definitely feel it in your hamstrings. Then after about 5 seconds of holding the position, try straightening out your legs for an even deeper stretch while remaining bent over.
Quads: You might remember this from middle school. Hang onto something for stability and hold your ankle while kicking your opposite foot back. Hold for 10 seconds then switch and repeat.