To drive to Angus, you can take the A90 road from Dundee or the A92 from Arbroath. If you're coming from Glasgow, take the M80 and then the M90 towards Perth, and then join the A90. If you prefer scenic routes, take the A93 through the Cairngorms National Park.
To get to Angus by rail, you can take the train from Edinburgh or Glasgow to Dundee, and then change to a local train to Arbroath or Montrose, which are both in Angus.
If you're visiting other landmarks in Scotland, like Stirling Castle or Loch Lomond, it's best to drive to Angus through the A90. Alternatively, you can take a train to Dundee and then rent a car to explore the county.