Because your mind is constantly active, a mindfulness practice has to be a constant practice. This is especially important if you feel a constant suffering. If you have generalized anxiety, broken heart, depression, or other such modes of constant suffering, then you are already experiencing a sort of constant mindfulness. Everything you do is affected by the constant experience of suffering. You need a break.
A constant mindfulness practice is just like a constant suffering practice. Instead of just suffering anxiety, stress, and sadness, you use those feelings to fuel your constant mindfulness practice. As you pay attention to the feelings, you don’t get carried away by them. You can breathe in and out with them and see that they won’t carry you away. You can be there with your anxiety, sadness, stress, anger, shame, guilt, or whatever is trying to carry you away. They come and go in your mind, your mind is constant.
The constant mindfulness, your constantly noticing your experience, brings with it an acceptance of the circumstance. It brings compassion for the circumstance. It brings hope to the circumstance, as you watch the feelings come and go and transform into other feelings.
It’s not any extra work to be constantly aware, constantly mindful. It is a lot of extra work to constantly suffer. When you practice constant mindfulness and the suffering eases or leaves, your constant mind remains, mindful and peaceful.