[tex]( x^{m})(x^{n}) = x^{m+n} [/tex], which means when your operation is multiplication addition of exponents.
[tex] \frac{ x^{m}}{x^{n}} = x^{m-n} [/tex], which means when the operation is division subtract the exponents.
[tex] xy^{2} =x^{2} y^{2} [/tex], which means when the operation is multiplication and your bases are not the same (like variable and numbers) just raise it by the exponent given. (Same with fraction/division).
[tex] (x^{m})^{n} = x^{mn} [/tex], which means the exponents are inside and outside the parentheses it should be multiplied.
Hope I helped. That's not all :)