Welcome
I'm afraid there's not really much you can do until you get him neutered. After they're neutered, it can take awhile for their hormone levels to decrease. After that he should stop mounting everything.
Like FlickeringHope said, you can try giving him a stuffed animal to take his frustration out on, but it's not a guarantee that he'll leave your feet alone. I'd recommend getting him neutered as soon as you can.
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.