Stupid question but where does one stick one's thermometer when measuring basal temperature??

[Banana79]

...

Under the tongue

phew

Or in the ear (if you nick your child's thermometer, as I do)

No you should not use an ear thermometer - not accurate enough as can be affected by room temp etc apparently.

Yes under tongue, same position each day, or for more accurate results vaginally (personally, I have never done this, but fortunately got reasonable results with under tongue). If you are a mouth breather at night, the vaginal route is more recommended!