Games should be played on rectangular mats measuring 6 feet by 3 feet. At
each corner of the mat are straight lines drawn at right angles to the mat’s
diagonals at a point 3 feet from the centre of the mat. These are called
baselines and they and the edges of the mat constitute the boundaries of the
field of play. Whenever possible mats approved by National Associations and
currently made of felt should be used.

Or, as it states in the Rules of Tiddlywinks (Simplified Version): “The mat: the playing surface on which the game takes place.”

I took the next step in preparing to play “official” tiddlywinks by visiting a local fabric store and purchasing 2 yards of white “craft” felt. I selected white to ensure the maximum visibility of the winks and squidgers of all players. All of the winks and squidgers I own are of translucent blue, green, red, yellow, orange, or purple, so they ought to be easily distinguishable on a neutral white mat.

I am considering demarcating the baselines with narrow pieces of black felt rather than marking the mat with ink or paint. That way I can remove them if I decide they are unnecessary or if I choose to play (or invent) any tiddlywinks variants (or perversions as they are known).

[Tiddlywinks rules can be downloaded here.]

Hm… Would a shot glass suffice? (The one shot glass I own deviates a wee bit because it is a measuring shot glass - 60 mm high, 50 mm diameter at the top, 35 mm diameter at the base.)

Of course, one could always resort to the Rules of Tiddlywinks (Simplified Version) for the equipment descriptions: “The pot: the container into which the winks may be played.”

NB: None of my tiddlywinks equipment conforms to strict regulations. Alas.

[Edit: The aforementioned tiddlywinks rules can be downloaded here.]