What does "in due form" mean?
To All whom these Presents shall Come—Greeting ,
Know Ye, THAT SEBRINA LANE whose official signature appears to the instrument of writing hereto annexed, was at the time of affixing the same thereto, the duly appointed deputy clerk of the Superior Count of Fulton County, Georgia as appears from the Records of this Department, and that her/his attestation is in due form .Therefore, all due faith, credit and authority is and ought to be bad and given to her/him.

Question

What does "in due form" mean?
To All whom these Presents shall Come—Greeting ,
Know Ye, THAT SEBRINA LANE whose official signature appears to the instrument of writing hereto annexed, was at the time of affixing the same thereto, the duly appointed deputy clerk of the Superior Count of Fulton County, Georgia as appears from the Records of this Department, and that her/his attestation is in due form .Therefore, all due faith, credit and authority is and ought to be bad and given to her/him.

Answer

In due form = in the proper form

The legal document has been written correctly and all needed information is contained in it as required by the law.