The first step toward building trustworthiness begins by building credibility in your resume. Rather than claim you have expertise, build a case to show you actually have it. As an example, show the credentials on your resume rather than claiming you are an expert in the field. While slightly exaggerating the duties of a previous job is somewhat expected, since hiring managers know you want to make yourself look good on paper, it should go without saying that putting false information on your resume is not only a way to not impress a hiring manager, but could even give you a reputation as someone who is untrustworthy and does not belong in your industry.
Although the interview is where you want to sell yourself to the hiring manager as the ideal job candidate, there is a fine line between explaining your skills and abilities versus raising a level of skepticism that you are "too good to be true." If you're asked a question that is hard to answer, give a straight honest answer rather than attempting to dodge the question by pretending you have knowledge or work experience in something that you don't really have.
Ask and listen
It may seem counterproductive to the interview process, but according to Harvard Business Review, asking the hiring manager for advice about the job you're applying for can make you seem warm and competent. When asking questions, show that you are interested in the hiring manager's responses by fully listening. Interviewees will often appear distracted because they are already concentrating on the next question they think the hiring manager will ask.