As long as you know your 1-4 times table, the below trick can allow you to use your fingers as human calculators. It is a simple technique to master and with practise,
you use it as a mental aid in remembering or visualising the 6,7,8 & 9 times tables.
Another video showing the same technique, but this time with the hands facing towards you.
The above technique will work for the 10 times tables as well.