Starting Clomid

Ch

Okay so my husband and I've been trying to get pregnant now for about a year the doctor decided to start me on Clomid which I started my period on the 17th it says take it on the 5th day of my cycle which is the 21st and I'm suppose to start having intercourse on the 27th thru the 3rd every other day but we are gonna start on the 28th

My questions are:

Anything else I should know besides what my doctor has told me?

Also should I use preseed during this time?

What prenatal vitamins do you suggest?

Anything else I should try?

And also if anyone has tried Clomid how many rounds were you on before coming pregnant?