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Dont worry too much about up and down as it's all a matter of hour you turn your head or the chart and on which side of the telescope you are. EQ mounted Newts are a good example.
Left/right reversal is another matter entirely and no matter how you turn any chart it will always be back-to-front (ie mirror reversed).
Any ODD number of reflections create a mirror reversed image. eg Refractor diagonal = one relfective surface. eg. SCT with diagonal = three reflectives surfaces.
Any EVEN number of reflections create a non-mirrored or corrected image view. The view could be upside down and usually is but it depends on how you turn your head with respect to the eyepiece and at what angle the eyepiece is with respect to thew ground. eg. A Newtonian reflector = two reflective surfaces.
Some astro software can now can print reversed images to match what you see in a single mirror finder or refractor or SCT with a diagonal.
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