First-Middle: Last, Beneficiary is the most common way but here are some examples if you can’t use this configuration:

First: Last, Beneficiary
First-Middle-Middle: Last, Beneficiary
First-Middle: Last-Last, Beneficiary
First-Middle II: Last, Beneficiary
First-Middle Jr: Last, Beneficiary

If you don’t have room to write the full word ‘Beneficiary’, the abbreviation is ‘BENE’.

The beneficiary signature is important on the back as it identifies the living beneficiary as the one making the request from the strawman account number.