1. Follow the POH....so many variations on a theme out there that one must be specific with each type
2. But for me the key issue (which is also reflected in pretty much every POH i've ever seen) is don't be in a hurry to go flying....let the engine warm up properly and then some too
It certainly adds a few more clicks of the hobbs this time of year to get everything nicely settled, but the pleasure of cruising in that crisp winter air always makes it worth while