Best tools and ways for a diverse team

I highly suggest that you use a version control software like Git* that both of you commit your code changes into, so that you can keep track of changes. Depending of your skills set up a local dev environment, so that you don't need to SCP/Git everything all the time to see the changes. That will loose you a ton of time and hard to keep track on what files you or your design guy uploaded.

You can set up a CRON script running every ~30min to make a "git pull" request so that your AWS server always have the new data, if your client want to see the demo.

*You can use Bitbucket (free up to 5 people) or Github (free up to 3 persons).

If you our your colleague don't know Git (CLI) you can use a client like GitKraken.