1. I should add that it’s important to maintain at least 5 transports in the Japan Sea and don’t build anymore ICs in the mainland.
2. Should have at least 10 INFs each in Persia, SinKiang and Yakut, then you could build tanks in Japan and INFs everywhere else (You need at least 2 to 1 ratio of INFs to tanks to attack Russia, so build some tanks when you can afford them).
3. Put your planes in SinKiang when they’re not needed to defend Japan Sea.
4. If Russia is defending the 4 surrounding territories with light forces (1 or 2 INFs) but have a large force in Russia itself, then capture as many of them as you can using just enough INFs and planes only. DO NOT use your tanks in this case.
5a. If Russia has a large force in Kazakh or Novosibirsk, strafe it (hit for 1 or 2 turns then retreat) with everything from the two adjacent territories (But use just 1 or 2 planes if it has AA. In that case wait for more tanks from Japan. Tanks from Man. can reach Novo or Evenki, so it’s possible to strafe Evenki with these tanks and from Yakut alone, depending on the size of the army in Evenki).
5b. Be careful not to capture the territory if Russia has a large counterattacking force.
5c. Retreat to Persia or Yakut after the strafe as SinKiang will be reinforced by own IC and from FIC. You might also want to land your planes in Yakut or Persia depending on the threat on SinKiang.
6. Hopefully Germany can hold out before you can capture Russia. Hope this helps and keep us posted. Good luck.
