Tracking temp

Br
I'm 8 days late today I'm just gna say I'm skipping my period this month cause I can feel it no where in sight ( still hoping for a positive blood test tho ) but for next month  I read it's the best way to see if you've ovulated ..... How do I track it ???? I know to buy a thermometer lol but do I start a certain day ??? Do I do it every day any tips would be greatly appreciated thanks !