I make it more sample so that it is easy to do and less resistance to do also. I think that can help me to build up the habit of eating a breakfast.
For example; a five foot tall, hundred pound woman who works in an office and gets only a few minutes of exercise on the week days may need much less breakfast than a six foot tall high school athlete.
My rule has always been, eat enough to feel like you aren't hungry, but not so much that you feel heavy.
I eat mindfully and without distractions (such as reading, or my phone or the TV) as that’s the only way I’ve found that I can really know when my body is satisfied.
Not easy in the beginning but so worth the effort. Food is more of a joy now.