I'd say it's taken me a little over two years where I consistently keep the Jordanville rule in its entirety. So don't try too much at once.
For me it was always doing the whole evening prayer rule, it's just that I started out only doing it one or two nights a week. Then later I added one morning a week, usually Saturdays since I didn't have work or school then. Gradually I have just been adding days, until now it is a natural part of my day and I notice if I forget or get too busy.
Another thing as a tip that has helped me to do the whole set of evening prayers is to not wait to do them until right before I go to bed. I usually do them about two hours before I go to bed, so that I'm not so tired that I struggle through them trying to stay awake, and also I don't have the excuse that I'm just too tired to do them.
I still struggle with the morning prayers more than anything, but God helps.
Finally, I don't do the rule if there is something else prayer-wise going on that morning or evening. For example, if it is Saturday evening, instead of doing the evening prayers, I just spend that evening doing all of the preparation prayers for communion. Between those prayers and attendance at Great Vespers, I have peace. Sometimes if it is the liturgical morning (AKA evening) of a particular saint or event I love, then instead of doing my evening prayers I will sing an akathist for that day, like the other week I did the akathist for the Holy Protection of the Mother of God, and then preparation for Holy Communion. Also, Sunday mornings or the mornings of a liturgy during the week, I wake up and go to matins the liturgy. In those cases, those are my morning prayers.
So basically for me, as long as there is some kind of prayer going on for at least the time it takes me to do my normal rule, this is completely acceptable. I'm still new to the faith and don't want to overburden myself to the point of spiritual burnout, because I'm not a monk and my icon corner isn't Mt. Athos. Just pray with faith and love, and over time God supplies the discipline. Trust me, because before becoming ORthodox I never took the time to pray every single day. God can do amazing things!
I hope that me going into this kind of detail isn't construed as me being too public about my prayer life, I can just remember a couple of years ago wishing for more detailed guidance about realistic goals and what was expected of me. So my only hope is that this look into my prayer life will help someone come to understand the "feel" I've gotten for ORthodox prayer life over the last couple of years, which is quite different in many ways from the Protestant "quiet times" of personal Bible study and confessions and intercessions. The transition was something that took a lot of adjustment for me, especially after years of not regularly praying.