Factorization of a trinomial can be achieved by using the standard method of appropriately "splitting the middle term" or by this method as shown in the video. This method is essentially similar to the standard one. It involves splitting the first term (containing even powers of the variable) and then using the terms so obtained to form imaginary factors. The third term of the trinomial is then split and the values so obtained are substituted in the imaginary factors term by term until the correct middle term is obtained. As stated at the end of the video, practice can help the user attain the solution a lot quicker without having to try many substitutions.