1. Create a new Twitter account and lock it down
2. Login to your "regular" Twitter account.
3. Submit a request to follow your new account
4. Login to your other account and accept the request
That lays the foundation on which you can build the house, which is discussed below...
1. Create a script that reads your Twitter DM inbox
That script should be written to look for specific content in order to perform specific actions. Do not make it blindless accept commands and execute them. You "can" do that, but it's a very bad idea. Murphy's Law will show up and ruin everything. Start simple. make your script look for "reboot" and just do a reboot of the computer.
2. Schedule your script to run on a regular interval, such as hourly.
3. Make sure your script deletes the DM inbox item after it's been processed.