Is EWCM a must!!!TTC?

Please i will like to know if egg white cervical mucus is compulsory to be discharged be4 or during ovulation.As for me,i hardly discharge ds during O but it occurs in some cycles but cant remember if it was during O or not.Instead i have creamy discharge which comes all thru cycle.Am ttc and my MP starts 2day 9march.Whn is my most fertility day?Since my partner is always busy and not always around,pls advice on which day to start having ahead of O since sperm can live up to 5days.I will be going for my FT on the 19th hopefully.Want to know all these Pleaseeeeeeeee