Rajat Umrao:
Cleared my CKS exam recently. Adding some points based on My experience:
• As everyone else added about slowness(its slow for real, i attempted at 2am), its really crucial to take that factor in mind as going through Firefox tab / scrolling / editing is slow enough to eat up ur time, so be precise in ur course of actions.
• Make sure you practice enough on mock exams labs and killer.sh simulator. I being a Mac user for a while found it really tough to train my muscle memory to use shit+crtl+C instead of command+c (costed me a few secs everytime)
• I would also highly recommend to go through killershell scenarios as well at least twice or thrice.
• You will hardly get any time to revisit solved questions so make sure you do it perfectly in one go (very less chances that u will be able to validate anything) and target high weightage question first.
• Revalidate you context and for questions involving file modification u need to be on control plane nodes make sure to come back to base machine every-time.
• Be extra careful in deleting any resource as there is no way to reset anything. Try adopting to crictl instead of docker.
All the very best with your certification Journey. 
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