Are there practices I could do to balance the energies so that my mind will be more alert and my attention will be better?

260966725_6c10456c48_oQuestion: Rinpoche, I would like to sleep less so that I could have more time to practice. I don’t want to waste this precious life! I have chronic illness that leaves me so fatigued that I am unable to concentrate my mind. I become very dopey and drowsy. Do I just have to accept that this is the ripening of karma, and that although it seems as if there is time for practice, I must sleep? Or are there practices I could do to balance the energies so that my mind will be more alert and my attention will be better?
Garchen Rinpoche: You should reflect upon death and impermanence and upon karma, or cause and effect.

If you do not purify your mind now, you will take your afflictive emotions with you into the bardo where they will manifest as frightening perceptions, plunging you into the lower realms.
Even if you cannot always sit up and meditate, you should always remember death and impermanence. To the best of your abilities, you should practice virtue for as long as you can. If you have to sleep due to your illness, remember your practice as you fall asleep and try to fall asleep with awareness, or at least with a virtuous mind. When you wake up, immediately remember your practice. Ideally you should wake up with awareness, without giving rise to ordinary thoughts. 

Another good method to maintain awareness is the OM AH HUNG recitation. You can practice this with each breath you take.
You should practice the OM AH HUNG recitation as you fall asleep, and eventually you will even remember it during your dream. You must practice according to your physical condition, but do the best you can. If you cannot sit up, you do not have to force yourself; you can also sustain awareness while you are lying down. When you maintain awareness, recognize each and every thought that arises.

You should also try to discipline your sleep. You should definitely not sleep less than five hours, but also no more than seven hours.
If you have a lot of work to do, you can adjust the hours of sleep accordingly, but you should keep it to a certain limit. If you do not have a lot of work to do, you should try to sleep less. It depends on your lifestyle.

But even if you have to work, you can always practice the OM AH HUNG vajra recitation, since you are always breathing.
You can align each breath with OM AH HUNG. You should also remember your Yidam deity and recite a few mantras during your daily activities. What is most important is to maintain awareness, to not fall into a lack of mindfulness. If you remain free from distraction, there is no other meditation than that.