Start with construction. Is there a full top plate, a three-quarter plate, or separate bars and bridges? Full plate with a pierced balance cock and a chain running to a cone suggests English fusee work; separate bars with a going barrel suggests Continental practice after Lépine.
Identify the escapement next. A crown wheel under the balance means verge. A cut cylinder on the balance staff means cylinder. A pivoted lever with two pallet stones means lever — and the pallet fork's orientation distinguishes English right-angle from Swiss straight-line layouts.
Then the winding and setting system. Key wind and key set through the back or dial, negative-set stem winding, lever set and pendant set each carry period and market information.
Only now record the markings: plate signature, grade name, jewel count, adjustment statements, patent numbers, import marks and punch marks. Photograph them rather than transcribing from memory.
Finally, treat the case as a separate object. Its hallmarks date the case; matching case and movement configuration supports, but does not prove, an original pairing.