I recommend checking out Musings by author, teacher, translator—and blogger—Ken McLeod. An excellent 
teacher, McLeod does just this in the vast majority of his blog: He teaches. Through simple practice tips and personal reflections, McLeod strikes an impressive balance between simplicity and depth which makes his blogs both instantly accessible as well as very useful. It is very practice-oriented and can serve as a great online resource for any regular meditator with an internet connection.
While his recent Tricycle Online Retreat contained lengthy in-depth talks on his translation of the 11th-century Indian Tilopa’s Ganges Mahamudra text, Ken’s blog often contains much simpler references. For example, in November he posted a blog using the fairy tale about Goldilocks and the three bears to explain the Middle Way.
In his most recent post, he discusses the topic of “capacity” as it pertains to meditation practice.
In a previous note, I talked about willingness, know-how and capacity as they apply to practice. Here, I go into more detail on capacity.
Capacity has four dimensions: depth, staying power, versatility, and resilience.
To develop depth, let your attention rest on the breath (or other object of attention) and let the object completely absorb you. Do this for short periods, being clear and aware. If you do this for too long, you will likely fall into trance states, a form of dullness, or start to block experience, a form of suppression.
To develop staying power, rest in the experience of breathing, letting the resting become more and more complete, resting with whatever arises, relaxation, tension, etc. You can do this for longer periods, but only as long as actual resting is happening. When you aren’t able to rest, take a break and come back.
To develop versatility, rest attention in the experience of breathing in different situations. Begin with easier situations and extend to more challenging ones. Again, short periods of clear stable attention are better.
And to develop resilience, learn to recognize the rhythms of practice, work deeply when conditions are right, and take a break when you feel dull, brittle, or tired. Resilience develops through the combination of making efforts and taking breaks before the effort causes any damage.”
Visit Musings here.