ttc and ovulation

day

i will be 40yo in nov. we are ttc twins. i am getting a regular AF, on time every month. my concern is that i don't think i'm ovulating. my CM is always creamy. i have 3 children and i knew exactly when i was ovulating and conceived without difficulty. the doctor said all my plumbing is working and it is safe for me to TTC. i want to begin taking clomid. does anyone have any kind of advice for me?