Using “lol” is a similar thing I like to do and recommend. It’s basically the same idea as the smiley face and can also be used to lighten the mood. A good “lol” placed in a text message shows a woman you’re making a joke. It’s not literally meant to mean that you’re “laughing out loud,” but it has transformed more into meaning that you’re joking or find something funny. (The same thing could be said for using “haha” as this is interchangeable with “lol.”)
On the day of the date, you want to shoot her a text, preferably early in the day and long before you’re going to meet up. This ensures you that it’s still on and tells her that you’re still in. She’s most likely doing the same thing that you are: waiting for that text so that you both know for sure that you’re both still in and not going to flake. By doing this, you almost guarantee a no-flake scenario between the two of you.