In addition to tools, bear in mind the 250 Rebel has no oil filter and thus many of us change the oil as often every 2000 miles, or even for a few, 1000.
In case you didn't see this in the owner's manual, when checking the oil level, hold bike upright, not on side stand. Unscrew and wipe off the dipstick and put it back in but do not tighten it at all...Just rest it on the top of the hole where it fits into...I generally straddle my bike and just reach down to do this check.
Also note that there are two bolts to remove before draining the oil. They are very close together on the left front bottom of the crankcase.
Best wishes with your ride.
Grace + Peace, Bob
2007 Honda Rebel 250 - Red. Stock.
I'm 83 and still riding