Must be designed for lifting and handling, mostly meaning supporting the compressor weight from skid corners, and from any lift lugs, with a safety factor of at least 2 when lifting. Also design end bars and frame for winch loads when pulling onto a truck, or dragging along the ground at the site, for example. Vibration possibilities when supported at anchor bolt locations during operating case should be very limited. Contact area of skid main frame beams and major lateral bracing beams with the future foundation should be high. Anchor bolts, hole sizes and locations should be designed for short circuit torque loads x 2. Provide numerous anchor bolts all along skid bottom so positive contact with the cement or epoxy grout of the foundation can be assured throughout its life. Thermal effects normally don't have any effect on the skid as ambient temperature extremes are accomodated by normal hole-bolt clearances, but holes could be slotted, if a horizontal growth problem is suggested.
Only put off until tomorrow what you are willing to die having left undone. - Pablo Picasso