Simple!
Since we can observe that they all have the same denominators (bottom part) we can just observe the numerator (top part)
6 is indeed greater than 5, yes? So we can safely say that
6/8 > 5/8
Now the for the second part.
6 is smaller than 7, yes? So we can make the observation that
6/8 < 7/8
Hope that makes sense! (Be sure to thank me, plz)
P.S. If you want an example of unlike denominators, let me know.