I always start by using a veggie wash (I like this one) on my green beans, and giving them a good rinse in my colander. Drain.
Transfer washed beans to a cutting board. Using a sharp knife, trim off any funky looking ends.
My preference is to move the beans into a large bowl so I have room to work, but you can also save yourself a dish to wash, and just drop them straight into your air fryer basket if you prefer. Drizzle 1/2 tsp or a few sprays of olive oil to coat the beans. I highly recommend this glass sprayer. Sprinkle 1 tsp of seasoning salt and toss beans until evenly coated.
I have a 7 quart air fryer basket, so I can easily fit 2 cups of beans in it. If you are doubling this recipe, or using a smaller air fryer, work in batches.
Air fry at 400 degrees for 6-8 minutes or until beans start to blister and crisp up to your desired level (if you like them to have some softness, cook them less, if you like extra crispy green beans, cook them 1-2 extra minutes). Keep a close eye on them so they do not burn. Tip: open the basket at the halfway point and give it a good shake to mix the beans around a bit and help prevent scorching.