Flip coin or roll dice for each team
Winning team can choose to call “Axis” or “Allies” or “Pass”
Once a side has been called, the other side will be getting resources if any
Choosing team calls “Axis” (meaning Allies bid of 0 or 2)
Other team responds by accepting Allies as Out of Box setup or offering some amount of IPCs to the other team to PLAY the Allies (thus taking the Axis)
“We will play Axis, and Give the allies 17” (binary choice; either choose the Allies, or raise the bid to the allies in return for playing the axis)
No cash can be kept
No change will be given
No bases or factories can be built
Like units only with like units (navy units added where you have like navy, land and air forces where you have at least 1 ground unit in a territory at game start)
Only 1 unit to place per territory* (this is a tournament rule; you could also permit stacking but it makes the bid quite different)
therefore, bids such as 2 (and 11, and 17) do not divide optimally into 1 or 2 specific units some money will be lost
Everyone seems to differ on whether the bid is needed, but not necessarily on where. I have seen some players give it to the US or China, but the prevailing wisdom is that the best use of the bid is to buy a sub, destroyer and some ground units for UK in north Africa. A UK destroyer can protect the Canadian destroyer, or the Cruiser in SZ 91, so that stuff is more likely to survive and become the nucleus of your new fleet for later in the game.
Even better, if you can get some ground units or Taranto add-ins (Tirano Suggests- 1 armor, 2 artillery in Alex, Egypt, Sudan, 1 DD with Cruiser or a sub etc for 15-17 bid G40), then the Italians never really have the odds to become a raging threat in the Med, and they are less likely to get income over 20 at some point. With the extra bid pieces, the war for the middle east is more of an easy win, so you can establish your bases in Egypt or your navy down there without many Italians surviving the first turn.
other popular places to put the bid units are to add Russian infantry or artillery, Chinese infantry, etc to add some staying power. Infantry are too weak and slow (and for USSR and China) support units might be better because they have so few. You still can only place infantry as china, note. The problem with this approach is making a difference with what you do place without it getting pretty quickly killed, but this could help you protect directly against Germany during Barbarossa somehow. There are tons of ideas about this but no consensus.
the bid helps handicap the teams and give the Allies a better chance at cracking one of the Axis. However, the bid doesn’t do a good job of addressing the dogpile and running program aspects of the game (attack Russia with everything is the critical path to victory)
G40 typical bids run over 15+, usually as UK units
G42 bid needs to be at least 8, to save the UK BB on G1.