The most important thing to understand is that log is a power (or an indice)
If you can remember this one it will help a lot. You can substitute other values in and use it for other questions.
\(log_{10}100=2\\ because\\ 10^2=100\)
Other than that you just have the log laws to learn
\(log_bX+log_bY=log_b(XY)\\ log_bX-log_bY=log_b(\frac{X}{Y})\\ log(X^y)=ylog(X)\\ \text{And the change of base law:}\\ log_bX=\frac{log_aX}{log_ab} \)