Or, if you have real small hands, get the chord you want in the second inversion. Now, add the flatted seventh, the ninth and the eleventh. You can play the thirteenth with your thumb (it is the sixth of the octave you inverted twice.
Now play the root with your left hand.
I know this may sound complicated, so I'll give an example. Key of C
Get C in its second inversion, so you are playing G-C-E with your right hand.
From here, you can add the Bb (flatted seventh), the ninth (D) and the eleventh (F). Move your thumb up from the G to the A. Now play a C-C with your left hand, and step on the sustain pedal. Here is your C13th.
Hope that helps.
Be Blessed . . . .