There’s nothing special about an outfeed table. But making it easily adjustable for a planer, when the outfeed wings move up and down, creates a challenge.
For the table top, I used a scrap piece of Formica covered counter top, so that the wood could slide easily across it. I used a piano hinge to attach the single leg, so that the table can be folded up when not in use.
Also the hinge is necessary when using the planer. As you constantly change the height of the planer bed, the outfeed table pivots up and down. These pictures show exaggerated views of how the tilting takes place.
To allow the table top to pivot at the outfeed wing, I bolted a lip onto the wing. Then I made some elongated holes in the lip, to match up with some ¼” dowels in the bottom of the outfeed table.