All hypothetical of course....
Research one of the officers or scientists (preferably photographed boarding a JANET flight or otherwise outside of the base)
At night...
Create a massive diversion that focuses security's attention elsewhere.
Sneak on during the diversion, coming from a remote part of the desert perimeter (having other diversionary "hits" on the motion sensors, etc. would
help here)...
Kill an officer or scientist (the one you researched), remove his right hand and eye. Don his outfit and appropriate his ID and creds.
Use a disguise kit to resemble the officer as close as possible.
Try to get in as quickly as possible.
For an exit strategy, you'd have to create more diversions to tie up security forces.
Possible Conflicts:
More biometric security measures other than palm and retina scan.
Later shift is more likely to know fellow personnel well, thus increasing the chances you are recognized as an imposter.
You'd have to pick a target that has the necessary access. Chances are, top access is only afforded to those who reside on the base and do not leave
the premises.
Unless the diversions completely tax the security infrastructure, you will likely be discovered quickly.
Getting out (and away cleanly) will be even more difficult than getting in.


They've got their own goat-starers, and are
better funded, and have probably been doing it a lot longer than anyone you'd get...but it's an interesting (and different) premise suggestion....