Not sure if I'll be downvoted for this, but "please" should be removed from your vocabulary.

It is a desperate word. It makes you seem submissive where you should be dominant. You can still be a gentleman, just word your questions differently so it doesn't seem like you are begging.

"Could you pay for lunch?" Is polite, but firm and in control. "Could you please pay for lunch?" Makes you seem broke and reliant on them.

Always say thank you however, as it shows gratitude.

Only a small tip, but I havent seen it mentioned yet.