I have always taken the following approach:
Claim: The Bible, and only the Bible, is the sole authority and source of God’s word.
Queries that MUST be answered to validate the sola scriptura claim:
A. Did the Bible come to man with a table of contents? The answer is no. But if he says that it did (and I have NEVER come across someone who says that it did), ask:
(i) when was the table of contents written? (ask for a specific date)
(ii) who wrote the table of contents? (ask for a specific name)
(iii) how could a table of contents be prepared before all of the books, particularly the New Testament, were written?
B. Considering the Bible specifically states that Christ taught the Apostles many things that were not recorded in the Bible:
(i) how can they say that ONLY the Bible is the source of God’s/Jesus’s teachings?
(ii) how did Jesus and the Apostles teach “the Bible” before 100 AD, when the last book of the Bible was not written until St. John did so around 100 AD (some scholars claim some epistles were written after Revelation, but for the purpose of these question, I assumed that Revelation was written last) while exiled on the Island of Patmos?
C. It is taken for granted that we actually have a Bible. Where does it state that God (other than the 10 Commandments, which came directly from him based on a literal reading of the relevant OT verses) or Jesus, or both, told ANYONE to write down what they taught so that there even be something that came to be known as the Bible?
D. Who chose the books to be considered part of the Bible? (ask for a specific date and person(s))
(i) If he names someone and a date, ask, by what authority, did that person have to compile numerous, independently written manuscripts, put them together, and say WITH AUTHORITY “this is the complete Bible”?
Remember, he MUST name someone in the Bible as stating “these books should be in the Bible” (or words to that effect), as sola scriptura, by defintion, means that the Bible is the only means of “hearing” God’s word. Of course, he cannot do so because a book cannot authenticate itself. A book is inanimate, and as such, cannot “proclaim” which books it should consist of, and state those books are the word of God, when, as mentioned above, all books were not written at the same time.
E. As each book of the Bible was written, especially the NT, who decided, upon the completion of each book that we use today as the NT, “that book that was just finished was inspired by the Holy Spirit and thus should be considered God’s word”? (ask for the name of that person(s) and the date(s) that decision was made).
The focus here is not on the entire Bible itself - the focus is on EACH book of the Bible, especially the NT, as it was being written while the Apostles lived and died.
E. Who determined how to interpret certain passages as what God intended their meaning to be? (as for a specific person(s))
(i) As an example, St. John describes in his Gospel the most complete accounting of the Last Supper. Three lines of “teaching” have resulted from what Christ did:
(a) during the Consecration, Jesus turned the bread and wine completely into his body and blood, so that nothing remained of the former bread and wine except what philosphers call “accidents” (meaning, strictly for the sake of appearance, the bread and wine looked and tasted like bread and wine, but they were substantively Christ’ body and blood). This dogma, known as transubstantiation, is taught by the Catholic and Orthodox faiths.
(b) during the Consecration, Jesus turned the bread and wine into his body and blood, but it was changed so that the result was the presence of break, wine, body, and blood. Although “accidents” were present for the body and blood part of the meal, but substantively, the substances of bread and wine also remained. This teaching, known as consubstantiation, is taught by the Anglican/Episcopal Church (and perhaps a few others - I don’t know who).
(c) during the Consecration, NOTHING occurred. Jesus was speaking completely in a figurative sense and he and his Apostles merely shared a last Passover meal together before he was to be killed. This teaching has no “consensus name” as far as I know. Having a wife who was a former Southern Baptist but converted when she realized the error of her ways

), I heard some members of her former church calling it simply “The Lord’s Last Supper”. It consists of baked bread and grape juice (no kidding - I am serious), they pass it out like our ushers collect money, except their “elders” go around the church with large plates and pass those down the pews for each person to grap a small paper cup of bread and grape juice. Before being distributed, it was set up on a simple table where the words “Do this in Remembrance of Me” are written on the front panel of the table.
Now, there is no other alternative. What happens MUST be one of the above: total conversion, partial conversion, no conversion.
As the text was obviously subject to different interpretations, who decides which interpretation is accurate and who gave that person the authority to teach his interpretation as accurate. Ask for name(s) and date(s) and remember that the answers to these two question MUST come from the Bible, as it is the SOLE source for God’s authority.
Most non-Catholics give up after A.
I hope this helps. When I put this together long ago, I started with a much larger collection of question, and then pared it down as time went by, realizing that in some instances, I could ask just one question and seek answers to different things without have to also ask different questions.