with texting you should be inconsistent, sometimes you text her all day, another day you reply to her and after 2 or 3 texts you say " I have to go now" , other times you ignore her...etc. you get the idea. and let's be honest here if you really have a life you are going to do this naturally.
as for flakes, girls are going to flake if they are not into you or whatever. as for scheduling you shouldn't plan a date far ahead; maybe try to not get past 2 days or 3 days. schedule weekends meeting during weekdays and weekdays dates during weekends; you get the idea.
as for confirming dates it depends but the best course is to text here in the morning if you have a night date something like " we still on tonight" if she is a new girl. that way you avoid wasting your time. and if she did not respond just make other plans and if she reply with a fake or can't make it you can give her another chance by something like " ok np; I will meet some friend then, how about day/time next week" .... if she replies with a confirmation then good and if she seems hesitant you know the answer...delete that number and if she contact you again then you decide to say yes or no.
it's not black and white...girls are going to flake. another issue is you shouldn't be too serious with texting. be funny, and avoid sarcasm because that sh!t don't translate well with texting...I've experienced with a lot of girls and the best course it to avoid sarcasm unless you and the girl know each other well. if she is a new girl avoid that sh!t.