Word of caution. Notice the After take off Checklist in the 737 makes no mention of checking the pressurisation instruments. Most pilots new to the game only check what the checklist tells them to check. For example bleed switches and pack position. People have died because the pressurisation during the early part of the climb after take off was not checked to be working. An occasional glance at the two pressurisation instruments is vital in the climb to cruise altitude. Helios comes to mind.