Do you need to solve a differential equation?
Is it a second order differential equation?
Is it homogenous?
If not, you will need the particular solution added to the homogenous solution.
To get the particular solution, you'll need to identify the driving force. What type of function is the driving force?
If it is a polynomial, follow this video. Remember to add it on to the homogenous solution. At^2 + Bt + C
If yes, does it involve complex roots?
Is it a system of first order DE's?
use the eigenvalues/eigenvectors method
Main topic
Is it a first order differential equation?
Is the DE separable?