Asking for a check professionally depends on the setting, but the goal is always to be polite and clear without interrupting the flow of the meal or the server's workflow. In a high-end or formal business setting, the most professional way is to make brief eye contact with your server and use a small, subtle hand gesture (like a slight nod or a raised hand) and say, "Could we have the bill when you have a moment, please?" or "We’re ready for the check, thank you." If you are the host and want to handle the payment discreetly without your guests seeing the total, the best approach is to excuse yourself from the table toward the end of the meal, find the server or the host stand, and say, "I’d like to take care of the bill now; please add a [20%] tip and I can sign for it here." Avoid shouting "Check!" or making the "signing in the air" hand gesture unless you are in a very casual, loud environment where verbal communication is difficult. Using the word "bill" is often considered slightly more formal than "check" in international or fine-dining contexts. By asking "when you have a moment," you signal that you aren't in a desperate rush, which maintains a relaxed, professional atmosphere for your guests.