What is the best way to handle a job interview that doesn't go as planned?

One of the important points to be kept in mind is that it is not about the content of your answers, usually how you deal with the interview, the questions matter the most. Many candidates try to 'over-prepare' for an interview with ready-made answers which never helps a recruiter to properly assess. So there will be other ways to evaluate the candidates such as provoking them, arguing with them, showing restlessness, showing dissatisfaction, etc. These are the tricks by interviewers that usually bring the true character of the candidate. So, the point is clear. Realize this and stay calm.

There is no shame in going back and offering a correction or addendum to something you said. A simple, hey I want to revisit this question as I realized that I went a bit too fast, or I did not give the problem the full thought, or I thought of something else that I feel is relevant. Better to rely on the interviewer recognizing you are a human being who corrects your mistakes than to have them think you don't know what you are talking about.

I recommend the CPR method to my coaching clients. CPR is Challenge, Process, Result, and is basically the same as the STAR method. The benefit is it’s one less thing to remember, as Situation and Task are folded into Challenge. It makes it a little bit easier to tell stories on the fly! The key with either method is to try not to ramble, and really hone in on the result that came about as a result of YOUR actions

Sarah, an enthusiastic job applicant who faced a challenging interview. Midway through, she realized it wasn’t going as she’d hoped. Instead of panicking, Sarah pivoted to asking insightful questions about the company’s goals and culture. This shift not only showcased her genuine interest but also helped divert from earlier hiccups. When discussing a recent project, she sensed skepticism from the interviewer. Instead of getting defensive, she probed further: “Could you share what you see as the ideal approach to such challenges?” This allowed her to understand their perspective and realign her answer. As the interview concluded, she warmly thanked them, reinforcing her enthusiasm. Sarah turned an initial setback into an opportunity to shine

What we often look for in a candidate will be the interest, passion, dedication, and interest to do the job / join the company / to learn the work. The recruiters and companies are aware that they'll have to train the candidates to make them fit for the role. So, the attitude will be an important key. If we have a person with the right attitude, we won't mind putting some extra effort into training them. Simple as that. Asking sensible questions about the company/role/challenges/scope etc in detail will help you in this.

Candidates often perform well in interviews and try to show their interest during that time. Consider the recruitment process as marketing yourself. Your resume is your brochure, interview is either a pitching or a discussion with your potential customer. There is something left - to follow up with the inquiry to ensure the conversion. A follow-up can be done in a different way by maintaining the contact and sending a thank you mail is one among them. Definitely, a thank you mail won't give you a job or won't be the only reason for getting shortlisted, but it will definitely contribute at least 1% in most cases. That 1% matters and it is worth your job and ultimately your life. :)

Before you go into an interview, remind yourself that you are not on trial. You have earned this interview, and you are interviewing the company/law firm as much as they are interviewing you. Practice creative visualization and smile while you are doing that. Picture yourself calmly meeting with your interviewer(s). Practice talking about your experiences and do this OUT LOUD. Listen to how you sound. Do you sound sincere? Are you speaking from your heart? Unless you are intentionally misleading your interviewer, any mistake that you make can be corrected. Veracity trumps perfection.