Eviction process Lawton, OK

[Jason H.]

I have been managing rentals for 5 years now, I currently have 11 Sfh rentals.  I have always screened tenants and have had great luck so far.  But, I have a tenant who has been staying a month behind on rent for a while now, I have tried to work with her, but she is only getting worse, she just informed me that she can't make a payment for 2 more weeks until she gets paid, by then she will be 2 months behind.  Keep in mind that she was telling me the same thing 2 weeks ago.   I need to start the eviction process, but never having had to do this, I am not sure on the exact process.  I believe I have to do the 5 days pay or quit notice, but i don't know if this has to be legally served or not.  Could anyone who has experience with this in Oklahoma, specifically Comanche County please give me some advice, I would greatly appreciate it.  Thanks in advance.