The WTBTS uses a multi-pronged approach when it comes to supporting their unique doctrines. Because they have a hierachical social structure the rank and file of the membership cannot interpret Scripture for themselves. They must accept the interpretations and doctrines that the leadership dictates. Anyone who "pushes ahead" of the organization and disagrees with the authorized teaching is removed from the congregation and isolated to prevent others even from knowing why these persons were removed. All contact with such persons is prohibited. Moreover, in a conversation you will almost always encounter at least 2 JWs together. In such encounters they will almost never concede to any arguments against their position because otherwise the other JW will most likely need to report them to an elder and this could potentially lead to being reproved or questioned.
They re-interpret words and passages and since 1950 they also use their Bible translation (New World Translation) to support their own unique doctrines. Their translation specifically tries to erase the scriptural evidence for Christ's deity, the existence of the soul after death, eternal punishment, the Trinity, etc.
Their leaders are adept at exploiting the fact that some words in a language can mean more than one thing, which can lead to various interpretations. In these situations they will choose meanings that support their preferred religious views, or at the very least undermine traditional interpretations.
The task of the apologist is to provide the reasons why their methodology and interpretation for each doctrine is not correct, and what the correct interpretation should be. This involves understanding their arguments and understanding the Bible and how to use the principles of interpretation (hermeneutics) correctly.
Some examples
The word “parousia” has two definitions in Greek dictionaries: coming and presence. In the NWT they only translate it as “presence” to support their view that the signs of Mat 24 are indicators that Christ is present and not that they indicate that Christ will soon be coming. They exploit the fact that some words can have both a literal and a figurative meaning and use that fact to interpret passages as being figurative rather than literal. They use passages in which an invisible “presence” can be legitimately understood to then assert that passages that refer to Christ's second coming are therefore also to be understood as invisible.
The word “eye” can be used in both literal and figurative senses, so they assert that passages that refer to Christ being seen at his second coming they say this actually means figurative sight, not that people will literally see him.
The word “firstborn” can be used literally and figuratively. So when it gets applied to Christ they claim it has a literal meaning to support their doctrine that he was created, rather than that he received the highest honour or position resevered for the firstborn.
The word "only begotten" (Greek: monogenes) can have a literal and a figurative meaning. When it refers to Christ they interpret that as a literal meaning to support their doctrine that Christ is a created being.
When the word “proskuneo” (worship) is used for Christ, they translate it as “obesience”; when it refers to the Father it gets translated as “worship.”
When an anarthrous noun (a noun without the definite article “the”) is used of Christ in John 1:1 they exploit that to translate that “the Word was a god”, even though most other times when God is used without an article they translate it as “God.”
The WTBTS uses the issue of using Jehovah in the NT as a smoke screen. It is undoubtably true that the Father is referred to using the term kurios and theos in some contexts. It is also undeniable that these same terms refer to Jesus Christ. They exploit this ambiguity to translate the terms kurios and theos as “Jehovah” specifically in places that weaken any interpretation that Jesus is divine or where OT quotes which use the tetragrammaton get applied to Christ. By relabelling those passages as referring to the Father, they weaken the evidence that Jesus is God.
They claim that they have faithfully translated the oldest manuscripts and thus they omit several passages (containing 240 Greek words) that are not attested in the oldest manuscripts. However, they use the word “Jehovah” 237 times in the NT when it has never been seen in any NT Greek manuscript.