Begin Another Section
After you become confident with one section, begin another. Start the process from the beginning with the new section, and proceed through the steps just as carefully as before. Resist the temptation to skip or brush over important steps, no matter how uncomfortable. This would lead to un-organistic playing.
Review often the sections that you have already learned. As you gain confidence, begin putting the sections together, creating new larger sections.
As you begin to focus on the whole, be aware of any new problems that may appear. If a new problem does appear, take care of it decisively before it has a chance to deepen its roots.