Section 254 is located in right-center field on the second deck of seating. This section sits directly between the right field gate and the center field gate. With most of the parking located on the East side of the stadium, it would make sense for you to enter the right field gate if you are driving.
From lots A, B and C, walk towards the stadium and go right until you find the right field gate. Alternatively, consider parking in Lot D on the north side of the stadium off of Congress St. From there you can walk towards the stadium and enter the CF gate. This would be the ideal option, although parking is limited in Lot D.