How would you approach a shop assistant at Selfridges (or any shop as fancy as it)? Can you share your success stories?
I do not have a problem approaching girls on street or in shops, but found it much more difficult with shop assistants.

Thanks a lot for your insights,
gent

The same way you would approach anyone else:

"Hi, hows it going?"
"Busy today?"
"Cheer up, why the glum face?"
"Hows your day been?"
"Busy today huh?"
"Do you think I look hot in these trainers/shirt/jacket"?

Just say hi to them, what you initially say doesn't really matter unless you say something prety perverted or terrible.

I do lots of day game at selfridge/harrods, send me an MP for next sess.

exit the changing rooms and say

"Excuse me, your stalls don't have any toilet paper"

Thanks guys, so basically indirect.
The thing is that they are usually around women only brand. So it is a bit tricky to keep our conversation naturally.

Could someone 'show off' how you succeeded with them? I'd appreciate that.

After some tries, I've learned some tips myself, so I give them to you here.

The difference between approaching women on street and shop assistants only exists in the beginning. After you open them properly, it's the same.
When on street, you need to have quite high energy to stop her, but in shops it's socially incongruent to have such high energy. You can save your direct compliments a bit later as well, as they sound too tense in shops.
Begin a natural conversation confidently and happily. I like asking 'so, which country is this brand from?', then if she says France, I would go, 'oh are you from France as well?'. That is one of natural ways to start talking about her.

Best,
gent

Good on ya gent, don't want ya to feel your having a conversation with yourself.

Good on ya for trying it out yourself and posting your results in opening in shops.
Crack on mate.