So on the weekends and days I'm off work I should temp at the same time I do monfri?
Yes, some ladies on here work in shifts (e.g. nurses) so they have figured a different system out that works for them. If you don't have this issue, I recommend taking your temperature at the same time everyday. I don't work Friday-Sunday but I still set my alarm to 6:30 (DH isn't thrilled about the weekend temps, but oh well). If you record a temperature 1/2 hr off from previous temps, you will get an open circle of fertility friend. Some people can still see the temp shifts with open circles, but I like a nice, clean chart.
ETA: I should add that you should get 3 hrs of sleep. Days when I don't, I still record at the same time and just note that I didn't get much sleep. If you drink the night before, your temp will likely be elevated so I note that as well. Other things like stress and sickness I've found to mess with my temps (like my chart this month is super fugly). Try not to look too closely at every single temp, but the overall picture.