If you’re using the mobile app, you can choose your model, capacity, color and carrier all before pre-orders open early tomorrow morning. Once you’re finished, choose the share button at the top of the screen and text it to yourself. (Or tap the heart icon to save it as a favorite, either method works.) When the clock strikes midnight Pacific, you can click that text, jump into the Apple Store app and place your order without having to pick the options at the last minute. Remember: Every second counts.

Source: Tech CNBC
Follow these tips if you're ordering an iPhone X tomorrow morning