creating address in wallet and sending how it works
Address are similar in a way to your bank account number, it just says where your wallet is. It differs in the way that a bitcoin wallet can have more than 1 address. Personally, I am receiving bitcoin on 4 to 5 different addresses. 

But I don't actually understand what you mean by creating new addresses to send bitcoin from, you only create a new address (or use an old one) when receiving bitcoin not sending one.