There were several different tonics/solutions but the one I remember using the most was take out the lens (after washing hands) over a white towel (in case it fell off of your finger - white is an easier background to see them on), give a quick squirt of saline, rub in a few drops of enzyme remover, rinse in saline, then store in the bottle (remembering L/R) until the next day.
Later on I just took them out and put in the solution (still remembering L/R) and they were good to put back in the next day.