Simplest way to design classic FSMs in Microsoft Visio?

I would like to create some basic Finite State Machines within Microsoft Visio. As an example, please take a look at the following:

Image source: "DFAexample" by Cepheus - Own work.

I tried to create my own stencil using simple ellipses, but the issue for me mainly lies in the styling of the connector curvature. The DFA example contains perfect arcs, but in order to achieve that I would have to manually adjust every connector. The state machine I am building is very large, so that isn't feasible.
Is there a faster way to do this?

Solution 1:

I'm using Visio 2013. The version you are using is unclear.

When you create a new file in Visio select the template Data flow diagram as shown in the below picture.

In case if you do not find the template in your Visio, you can download it by using the Search for online templates search box. Search for Data flow diagram.