JeffL:
With a cream, it sorta depends. With a tube cream (e.g., this Proraso product), I’d squirt a bit into a small bowl or, lacking that, the palm of my hand, and whip it into lather with a moist brush. With a tub cream, (such as this Taylor of Old Bond Street product), a moist brush swirled a second or three in the midst of the cream is enough to pick up enough to build a lather directly on my face, in a separate bowl, or in my palm. Building the lather directly with either cream isn’t really possible: the tube provides no surface to swish over, while the tub of soft cream isn’t great since you’d keep picking up more and more of the stuff while you lathered.
With a harder cream/soap hybrid (like this Proraso product) or a full soap (like this Crabtree & Evelyn product) I like to wetten the surface for 30-60 seconds before starting to create a thin layer of softened soap on the top. You can just drizzle some water on there, or if the soap’s in a large enough container, pour water over it and then drain when you’re ready to begin. Swirl a moist brush over it for 30-45 seconds to “load” the brush–since it’s noticeably harder than a cream, it will take longer to build up a good amount on the brush. From there, you can lather it up in your palm, directly on your face, in a separate bowl, or–if there’s enough “clearance” in the soap existing container, right on top of the soap itself (since it does take so long to “scrape up” soap, you shouldn’t have to worry about overloading it).
I’d probably rate palm lathering lowest–it’s just messy and obnoxious if you normally use your free hand to pull your skin around with, although it does make “feeling” the consistency of the lather much easier–and then say you have about even odds between face lathering and bowl-lathering. Face is faster, but it can be harder to really whip up a massive mound of creamy lather on the ol’ mug without covering your counter, ears, eyebrows, and mouth in it. Bowl takes a little extra time (~45-60 seconds to lather in the bowl, then another 15-20 to apply to the face from there), but you have somewhere logical for all the excess lather to sit between passes, letting you scoop up more if your brush itself runs low.
Edit: worth noting that I used all the above linked products personally and can vouch for the methods described for each based on my experience with my fairly hard Raleigh water. If you live somewhere with even harder water than me, I might recommend you avoid hard soaps and stiff creams (Proraso bowls and designer products like Queen Charlotte Soaps shave cream), as getting a really thick lather is difficult with hard water. Creams will lather well with almost anything anywhere. Also, the Proraso I linked above appears to have received a refreshed product (search Amazon for “proraso sensitive,” but since I don’t know if the formula changed along with the packaging, I’m hesitant to link it in the above explanations as it may not necessarily still be a “stiff cream”).