hi and welcome.
Having fertility friend is a good start. You take your temp with a digital themometer than goes to one decimal. take it every morning at the same time say 6:00am or as close to as possibile, if your kids wake you up before say 5. take it then and enter in FF the temp and 5am.
Read about charting CM
here
in FF if you click on sharing and then your homepage there is a link at the top. and post that here and we can see your chart