Become disciplined through Islamic methods
Two Quick tips: 1) Wake up for fajar - this is hard and hard things build discipline , but what if you don't have the discipline to wake up for fajar in the first place. Then ... 2) Build it through things that you can do, but are still hard like , fasting , reading Quran etc. Also don't forget to ask Allah for help , because this is our cheat code as a muslim