Visual determination of fuel on board

[aldoradave]

I have never owned a Cessna product before but I don't have any confidence in gauges no matter the bird. However, other than beginning every flight with full tanks how do you determine the fuel you have on board. For some of the singles I know there are "calibrated" dip tubes that are inserted into the fuel fill entry. And for my Seneca and Beech there were tabs that you could see.

But given the dihedral of the P337 and its single fill tube,it may be that the half full condition may not show up on the fill tube.

Can any of you give me a suggestion on what you do for this.

Dave Dillehay N84E

PS. Sorry if this has been answered before but the search function only shows gripes about gauges!