Essentially you will want to be exporting DWGs to your AutoCAD colleague, and either importing DWGs from them or Referencing in their DWGs and working on top of them. How you do this export will depend on how you are working in Vectorworks, in 2D or 3D.
If you will be importing DWGs, we highly recommend watching this video:
...and remember to NEVER import the DWG into your main, working Vectorworks file. Always use a new, blank file as the video describes.
If you will be Referencing DWGs into your Vectorworks file, take a look at this material:
https://serviceselect.vectorworks.net/training/tutorials/referencing-external-files/
Referencing DWGs into your Vectorworks is often the safest, cleanest way to get the AutoCAD info into your file so you can trace over it/refer to it.
If you have access to the Vectorworks Service Select website, you should watch this training session:
(If you are not already a member of the Vectorworks Community Forum, we highly recommend you sign up. It’s a great place to get answers and to assist others. Over the years it has been a great resource for finding solutions.)
Perhaps most importantly, do some practice exchanges with your AutoCAD BEFORE you MUST make the exchange work. Talk about the results to make sure that you are both getting what you need from the file’s you are getting. If they are not getting what they need, try adjusting your DWG export settings as this usually corrects any issues that they may have.
This material is also very much worth reviewing so you know what it possible: