You work 10 days on, and 5 days off. If your team hasn't been dispatched to a rig to log a well, then you just show up at the base and perform maintenance on equipment and tools from 8 - 5PM. This is the base routine.
However, the base routine is frequently interrupted for what you were really hired to do: go to rigs with your logging crew and log wells. You could be dispatched at any time, and with only 12 hours' notice or so. You might come into work at 8, find out you were dispatched to a job that evening, and spend all day preparing. Then all night driving to the well and doing the log, then coming back early the next morning. Usually the FSM will cut you some slack on not make you stay at the base all day for your regular baseline shift after you spent the whole night awake.
Always different. The field is the field. It is seldom predictable and requires WE's to problem solve on their feet. Sleep is never guaranteed but there are times for power naps - seriously logging wells takes a long time. My longest jobsite time was 4 days straight in the New Mexico summer heat. The Engineer will have a team - depending on the shop location - 1 to 2 technicians to help with rigging up/down equipment.
Here's an example: WE gets word that a drilling company needs a newly drilled well logged. WE and team load up the truck with necessary tools and equipment (work and food supplies) and head to job site. Depending on the sites readiness the WE and team could wait around or rig up immediately. Team sends tool string downhole and starts logging - depending on customers needs team may do this several times. Hole depth can range from a few thousand feet to 15-20k feet depending on geographical location. Once well log is gathered, WE will clean up and title the log document (put headers on it, identify key points in the formation, etc). WE will hand document over to onsite company rep and head back to the shop. At the shop the team will clean truck/equipment, document lessons learned, finish paperwork and either head back out or go on rest. Off days or non jobsite days (aka shop days) are spent cleaning/inspecting tooling and equipment.