There are various different ways to express the idea of being "familiar with the procedure." Some potential synonyms could include phrases like "well-versed in the protocol," "knowledgeable about the technique," "versed in the process," "acquainted with the method," or "experienced in the system." Other synonyms might include phrases like "adept in the procedure," "proficient with the process," "skilled at following the protocol," or "competent in the technique." Ultimately, the choice of which synonym to use will depend on the specific context of the situation and the tone and style of the language being used.