What works for me is to start with 3 days of nothing but meat/poultry/fish, fat, salt and water/tea/coffee. Getting the carbs completely out quickly clears the brainfog and cravings, and 3 days is easier to commit to. YMMV, but cheese & dairy stokes many peoples' cravings. Then move on to Atkins Induction or whatever worked for you in the past. I also found reading my old books, visiting LCHF websites and listening to podcasts is a good way to strengthen my resolve to stay on track.