Approach it like an exercise in Zen. Music is like that ocean out there. The further out you go, the deeper it gets. Forget about schedules, dedication and practice will lead to improvement before you even realize it. Work on any 3 chord progression in any key, that's most of popular music anyway. Learn this: I-IV-V or II-V-I, that works in any key and is 90% of what you need to know. If learning scales, forget about speed for now. Master playing one note soulfully with emotion and expression. Your voice will come, but you decide the path.