The first parameter in this table is required and the template will fail without it. All the other parameters are optional.
First positional parameter (optionally |1=)
Username of the sockmaster or suspected sockmaster
Just include the name, no "User:" or square brackets.
Second positional parameter (optionally |2=)
spi, suspected and default (nothing specified) - these are equivalent, and can be used if the user is still under investigation or has not yet been blocked or confirmed by checkuser.
blocked - this is used for sockpuppets that have been blocked on behavioural evidence (the duck test) or behavioural evidence combined with a non-conclusive CU result (such as Template:Possible).
proven - Behaviour is beyond reasonable doubt but there is no CU Confirmed result (CU may have given a different result).
confirmed, cuconfirmed and nbconfirmed - A CU has Confirmed that the accounts are related.
Third positional parameter (optionally |3=)
Evidence of sockpuppetry
This field can be used to link to the evidence of sockpuppetry, or to give a very brief summary (a couple of words). If this parameter is left blank and the sockpuppet investigation case page is a blue link, then a link to the case page is provided automatically.
Subpage name (just the master) of the SPI if not the same as the master
This field can be used to specify a different SPI page if the page is not named for the master in parameter 2.
This parameter can be used to remove the note about the account being blocked, such as when a version other than the default applies. Such as if an account is confirmed by a CheckUser but is left unblocked. This parameter works with all parameters.
Length of time the sockpuppet or suspected sockpuppet was blocked
Use this field if the sockpuppet or suspected sockpuppet was blocked for a specific length of time. This parameter defaults to "indefinitely". This parameter is ignored, and does not default to indefinitely, if nbconfirmed is used.
Custom category name for the sockpuppet or suspected sockpuppet
This parameter defaults to the category "Wikipedia sockpuppets of X" if the second positional parameter is set to "confirmed", and "Suspected Wikipedia sockpuppets of X" if the second positional parameter is set to anything else. Here, "X" is the username specified in the first positional parameter.