Basically, a Wabisabi transfer always has two inputs, and two outputs.

The inputs are the unspent ecash tokens which are destroyed, so basically a message and signature part.

The outputs are the new ecash tokens to be created, basically the blinded message which the mint is meant to sign.

Each ecash token has not just the blind signature, but also a commitment to a homomorphic encrypted value of sats.

With this homomorphic encrypted values, the mint can verify that the sum of the two inputs are exactly equal to the sum of the two outputs. Which prevents the unwanted inflation of tokens, without revealing the actual value of any of the four tokens of the transaction.

There are also zero value tokens which are needed to split up a single coin. For example, one input worth 5 btc, one input worth 0 btc, one output worth 3 btc, one output worth 2 btc. The mint verifies that 5+0=3+2, but has no idea what value any or the tokens have.