Questions about clomid

Another post on clomid because it's all new to me. My cycles are irregular.. 26-40 days long. I do get a period every month and positive opks but no pregnancy.. But here are my questions

1. When do you ladies usually ovulate on clomid?

2. Should I take opks? If so what cd should I start?

3. When should I see a change in my cycle?

4. Has clomid worked for women who have had a missed miscarriage and d&c?

5. Should I use sperm friendly lube and prop my hips up after sex?

6. How often should I have sex?

I can't start it until I get my period again so I'm just waiting. I'm on cd15 today. I apologize for all the questions but I wanna know what exactly to do ☺