best way to check the tranny fluid is to drive it ,say 20 miles or so until it is warmed up, then (with foot on brake of course) put it in park,reverse,drive,then back in to park. Leave the car running and get out and pull the dipstick, wipe it, re-insert it and then check it. Fell the fluid with your finger and judge if it is warm or hot and then see where the level is on the dipstick. And like In2Deep says, don't overfill.....it will cause foaming. The reason for driving the car and warming the fliud up is because the fluid "expands" when it gets hot, so if you check it cold you will be putting too much in. And use the ATF+4...it's expensive (about $7 a quart) but your transmission is worth it.
Former 2001 Chrysler Intrepid SE owner
Currently own a 2012 Ford Focus