DO NOT do this if you cannot do it SAFELY.
LOWES has a little $6 tester, with lights for 120v AC, 240v, etc.
Locate a convenient "Reference socket:
1. test between the large slot and the round ground,
1b. if it reads 120v or higher, mark it "X" for improperly wired.
2. check between the two slots (the power pins) for 120v,
2b. if it does not read 120v, mark it "S" for "switched".
3. Check the ground (round) to the shorter slot (the "hot" pin),
3b. if it does not read 120v, mark it "UG" for "un-grounded"
4. If it passed the above tests, mark it "AR" for your Reference (phase A) socket.
Then, to map things out, connect a "long-enough" extension cord to your "reference" socket (marked "AR"), and then drag the receptacle (socket) end of the extension cord with you to all the other "candidate" sockets of interest, using the tester (or an AC Voltmeter) to:
1. Start with one of the (usually) two sockets (repeat the tests for the other sockets),
2a. check between the two "power" pins of the candidate socket to determine if it is "live"
2b. if it does not read 120v, mark it "S" for "switched" and start testing another socket,
3. test between the small slot of the candidate socket and the small slot of the extension cord,
4a. If it is "zero", mark the socket "A",
4b. if it reads 240v, mark it "B".
4c. if it reads 120v mark it "X" for incorrectly-wired. Plan to get it wired properly.
5. test the other socket of the pair, which COULD be wired differently.
6. Continue on to another wall socket, if desired.
See SOC/GID-Meter and CAN-Do Info
2010 Prius, now for sale
2011 LEAF, sold in 2015
2018 Tesla Model 3
2014 Tesla S, Model 3 in 2019
Solar PV: 33 x 225W -> 7 kW max AC
To Sell: X-treme 5000Li EV motorcycle