Why does my dog step on my foot?

I have a 7 month old Westie, and for a while now when he walks into the room he walks upto my feet (where i am sitting) and steps on one of them and then lies down right beside them.
It doesnt hurt or anything, just curious as to why he does it.

I'm not sure why a westie would, but every large dog that I have known does it for sadistic fun

I may have heard wrong, but I did hear that it was a dominant behaviour?

Well I'd say you're wrong, but then I don't believe dogs are out to dominate humans!

Dogs like human contact, mine will sit on most people's feet if she wants some affection, or just somewhere to rest so she knows she's touching you.

but he is totally subservient to me.

If I'm sitting with my legs crossed with one foot in the air, my dog cocks her leg over & sits on the foot in air!! not quite sure what she's trying to do!!

I think largely for the same reasons we step on their feet.

While there is no doubt some dogs continually try to show their higher pack rank, I don't think it is done by stepping on feet.

this is deliberate by him tho
and he only does it to me, no one else in the house

Dunno bout treading on feet but ALL the Labs i have known lay, sit and or sleep on feet of people they like!

It is cruel to force a Lab to sleep on a soft, smooth surface. They will not do so unless forced.