To distinguished between dehydration lines and wrinkles, push gently against the lined area with your finger. If the lines are fine and they disappear or become less apparent when you release your finger, they are marks of dehydration. If not, they are wrinkles and more difficult to tackle.
To reduce dehydration marks, start using a good facial moisturiser daily, morning and night. You should also smoothen the lines around your eyes by using eye cream. I am currently using ZA's Future Defense Emulsion for moisturiser and ZA's future Defense Eye Cream and they are quite good. If you know of other good brands, feel free to share.
I do not have much experience with dealing with wrinkles, but according to some of my colleagues and personal research, you will need more potent skincare like anti-wrinkle serums, which reportedly help cells produce more collagen and protein to push out the lines from within. These work better on wrinkles that are not so deep. But for deeper grooves, a combination of Botox and fillers can eliminate them. Botox acts to paralyse the muscles and prevent further wrinkling, while the fillers help to fill and smoothen out the groove made by the wrinkles.

