BBT and actually taking my temp...?

Samantha • Mom of a beautiful 2 year old, Emmy. Trying to conceive miracle #2, TTC for a year so far with PCOS.
When you ladies take your temp do you put the thermometer way back by your "heat pockets" or do you just put it under your tongue? Directions with my thermometer tell me way back but sometimes I gag and I feel like maybe its not accurate.