Tajweed and its application can only be learned with a qualified teacher of which online Quran tutors & teachers are a prime example and alternative.
The rules themselves can be studied independently, but their correct application can only be done by listening to, reciting to, and being corrected by, a qualified teacher of the Quran.Unfortunately many do not know proper tajweed and this result in the direct inability to memorize the Quran. There are many schools that provide online Qaida course and opportunities to memorize Quran online. In the days of the Prophet Muhammad (SAW) there was no need for the study of tajweed because they talked with what is now known as tajweed; in other words, it was natural for them.
Centuries later now, modern Arabic has changed radically from the classical Arabic in which the Quran was revealed, and Arabs have to study tajweed, just in the same way that non-Arabs do.The first step is finding a qualified Quran instructor who will listen to you and point out your mistakes, and help you practice fixing them. You will need to learn the Arabic letters preferably by joining an online Qaida course or attending physical classes and vowels too.Then your task is going to be a little harder, but certainly not impossible. You will need to work on the pronunciation of letters by getting a description of the articulation points and practice placing your tongue, lips, or finding the place in your throat where the letter is articulated from, and compare it to the letter when recited by the teacher. Online Quran tutors & teachers can greatly help a person to memorize Quran online because these digital teachers are extremely qualified and learned scholars who have great grasp on the concepts of tajweed along with understanding of tafseer.