Always you can know something about what you’re saying

God says:

Sometimes it will be very clear to you what your tongue is expressing and other times you will have little idea but you can always have a general sense of the atmosphere the tongue is creating – sad, happy, announcing, reassuring, exclaiming, ordering and so on. As you try to sense spiritually what it is about, notice any pictures or words that come into your mind and consider whether these are relevant. As you ask for, and expect, wisdom and as you stir up your spiritual awareness, more will come to you.
But don’t expect learning in the spirit to be like learning in the natural!
A new believer can have great revelation and a seasoned believer very little; some tongues are about things too holy or too terrible to express; mostly I just want to be with you and love you.

You can use tongues to cheer yourself up and also to stir up your spiritual awareness. I promise you peace and joy as you enter in to my love!
If you are wanting to know what you are singing or speaking about you could try this:
Be like a bird circling around in the blue sky getting its bearings and feeling the rush of the wind, feeling for the air currents and thermals. So you also survey the surroundings, view your spiritual domain (which is very expansive) and feel inclined to soar or to sweep or to view or to settle in a particular direction or on a certain high tree or cliff.
Take it in as you soar in tongues. Feel the currents and view the land.
What type of tongues is it? Happy, joyful, melodious, lamenting, hurt, passionate, concerned, distracted, fearful or in awe? Are you praising, worshipping, speaking, calling me forth – my help, my light, my glory, my salvation, my presence, my healing, my power, my kingdom, my return, etc? Do you know what unspeakable mysteries are in that ‘etc’?!