What tips do you have to navigate VES or Veteran Evaluation Services?

I am assuming this focused on preparing for a VA disability initial submission, follow-up or appeal to the Department of Veterans Affairs.
1. I highly recommend contacting DAV, VFW, or any other veterans service organization [VSO]. They have offices dedicated to assisting service members by translating the language of [US Code] Title 10 service-connected injuries and illnesses into [US Code] Title 32 VA disability submissions.
2. Ensure you have a copy [hopefully more than one] of all your service medical records and any civilian medical records during your period of active military service. I highly recommend making pdf copies of all records and storing it on a thumb drive.
3. Start the process no later than six months before your retirement/ETS. Your personnel office should be able to help you by providing information and perhaps contact info for VSO folks who are available to help you navigate the process and follow-up.
Thank you my friend SSG Carlos Madden for alerting me.

Get and keep copies of everything you send or upload to the VA. I can’t tell you how many times I have faxed papers with confirmed receipt and they still don’t know where it went. Never send small bundles of papers. Make sure that each is numbered with a breakdown of the numbering on the second or third page. This will give them quick access to notes on specific things being provided or contested. Summarize all your doctors appointments and test results for everything claimed. Get letters from doctors if they will not file a DBQ or ask for all documents from the office of the doctor. There are notes that will be there that you are unaware of. And get this book. It’s not cheap but it is the resource of champions!

Get access to all your medical records, get advice from others that have been through the process, and don’t wait until after you have officially separated to start the claim process if possible.