You might consider carrying a couple of empty gas cans to drain the old gas into.
Also drain any old gas from the carburetor.
Don't clean the sediment bowl because it may not reseal and then you have created a gas leak; don't ask me how I know.
As Hugh McKinney recommended below, make sure to check the oil at the oil level test cock.
If necessary remove the crankcase oil filler cap and add oil through the crankcase oil filler opening located near the distributor.
Add oil until it drips from the oil level test cock.
Make sure to check the oil in the air cleaner cup; clean the cup and add oil if necessary.
I have found air cleaner cups completely empty and dry, filled with water, and filled with dead bugs.
Open the oil level test cock to check the oil in the Powr-Trol.
If necessary remove the Powr-Trol filler plug and add oil until it drips from the oil level test cock.
Check the oil level in the power shaft clutch housing (PTO) by removing either of the two filler plugs.
If necessary fill with 10W oil to the bottom of the threads.
The power shaft shift lever must be engaged to the left for the PTO to operate.
Disengage the tractor's clutch lever and engage if necessary.
To operate the "live" PTO, pull up on the power shaft clutch lever located on the bottom right side of the battery box.
Check the position of the Powr-Trol pump shift lever as Hugh McKinney recommended below.
The photo below shows the Powr-Trol pump shift lever disengaged in the OFF position.
If you test the operation of the rockshaft hydraulics, the Powr-Trol Pump Shift Lever must be in the ON position before the tractor is started.
Once the tractor is started and running, the Powr-Trol pump shift lever can not be engaged.
Be sure to check the water in the radiator.
Hope this helps.