Stick the dipstick tool in till it hits the bottom of the pan.

Fluid level is measured from the bottom up.

REMEMBER >> fluid temp is VERY critical in order to ascertain accurate fluid level. In a perfec world > fluid is measured when it is at 80C. [that's what it says on the dipstick tool]

I used a infrared thermometer to get a pretty good ballpark temp of the fluid... run the car > get fluid hot > "ping" the tranny pan [fluid inside the pan should be same temp of the pan] ... I think the hottest I could get the fluid was 78C >> so I filled short of full mark