respond between 7-15 minutes on average. Just long enough to look busy but not enough time that she forgets about you. Don't use smileys. Don't use anything like lmao lol rofl etc. don't text anything that could lead her to not responding, like don't say to her question just your response and leave her nowhere to go without having to be the one to carry the conversation the entire time. Also try to lead the conversation, you are the guy you should be making her be interesting to you not the other way around.