Thor:
Thor lay flat on the bed while you're literally on top of him, like literally. He holds you so you don't fall.
Tony:
Tony placed his hand on your waist and other hand holding yours. But during the sleep, it always ended with you kicked Tony off the bed.
Steve:
You put your head on his chest and your hand hugging his waist while Steve lay still. Basically it's like a koala bear hugging the tree.
Bruce:
You two sleep peacefully with one person taking one corner of the bed. Sometimes you two moved to the middle and hugged each other.
Clint:
Clint likes to spoon you so that he felt safe. He thinks that he's hiding you but you think that it's like a female bird protecting her baby.
Pietro:
You two sleep hugging each other but ended up in weird positions. For example, your legs on his stomach and his legs on the pillow.
Bucky:
You would hold tight to his metal arm while Bucky hugs you with the other hand.
Thanks @beatz2014