To any student having trouble with multiplication, the first thing you should do is memorize your basic multiplication facts. All math from 2nd or 3rd grade on is based on these facts. You don't want to have be looking them up on a table or putting them into a calculator each time you need them. Just imagine doing a complicated Calculus problem and having to put 8 x 7 into a calculator because you never learned those basic facts.
When you start multiplying larger numbers, lattice multiplication may help you understand your work a little better. Lattice multiplication is also fun.
Below are two videos. The first will demonstrate lattice multiplication. The second will explain why it works.
WHY LATTICE MULTIPLICATION WORKS