Remember that more often than not the technical interviewers won't be prepared for you because they're probably more concerned about whatever's stopping them from shipping the next release then growing the team and the fact that you're taking time away from that puts you at a disadvantage.

You can counter this by showing what you can do and how you can help them right at the start. Bring your laptop and be prepared to show code samples, demo applications, documentation, training materials or whatever you else you can and jump on any opportunity to take charge and show your stuff. Try and promote a feeling of optimism and the sense that you take pride in your work.

If you get the chance to chat, ask about something they'e struggling with and relate that back to your own experience. Tell them about your struggles, how you kept your head and helped the team when things got tough and make sure they know how happy it made you when you finally shipped your last product. Real craftsmen will know what you're talking about and appreciate it.

Finally, do your research before you visit. If you can, ask for the interview schedule in advance and find out what you can about your interviewers.

This has almost always paid off for me. At one job I discovered one of my interviewers studied under Knuth. Early in the conversation he asked if I had any questions and I immediately jumped on that, asking him what it was like to work with him. He smiled and said that the hardest part for him was the effort he had to put into TeX and typesetting.

Be confident, but not arrogant. Make eye contact with the person you are talking with. Don't try and be too anxious and do something stupid like bouncing your knee up and down hitting the table or constantly rub your hands together (I've seen both things done during an interview and you just look rude). Research the business prior as most companies will ask you to explain to them what they do, if asked this question, it will make or break the interview.

Be honest as possible, but know when to not be too honest. Don't go detailing how you systematically helped the previous company you worked for spiral into bankruptcy or how you never got along with your boss. There is a line, answer their questions, but don't go into too much detail unless asked for it (it's rare an interviewer wants copious amount of detail).

On the honesty front, don't be afraid to embellish your experience and back story slightly either, but ensure that it's manageable embellishment. Because if you go claiming you have these amazing skills and they find out you don't, you'll be sent packing quickly and it'll be embarrassing for you.

Thank you so much!

I try to do as much research about the company as I can, so I can speak with some knowledge and have some questions for them. If I can I research even who will be interviewing me, so I know some of their background - not to let on, but to try to give me an idea of what kind of questions they will ask, based on the experiences they have had.

Practise multiple times beforehand with someone(s).

I try to practice with Cracking the Coding Interview book when I have time but I am not sure if that is sufficient.

That's a fine book, but I meant practise at a whiteboard with a real person using questions from that book.