Stoicism is a view about what is good and how to achieve it.

It's a virtue ethics, stating that who we are matters most. We want to have a "true and immovable judgement." Other life philosophies state that what is valuable are other goods like how we impact the world, what we achieve, and the rules we follow. Some of these points are good, but are not fundamentally good. According to the Stoics, what is fundamentally good is completely under our control, our character.

Hallvard J. Fossheim has argued that virtue ethics has a problem:  

In spite of all its talk of character traits, developmental processes, and the life of the agent, virtue ethics has failed to develop points of contact with how we can change the way we live and act. This criticism can be voiced as a claim that virtue ethics has been unsuccessful at relating to the concrete question of how we can realize good agential states.

Now, this criticism may be fair if it is applied to some contemporary academic virtue ethicists. They may be involved in a more theoretical rather than practical project. However, the ancients philosophers wrote a lot about how to be good. The Stoics developed their own theories of ethical development and of course talked quite a lot about how to become virtuous.

Epictetus has a number of heuristics we can begins to apply to our lives, by reading Marcus Aurelius we can get a better sense of how an emperor thought about becoming better, and with Seneca we can go consider concrete cases dealing with grief, fame, friendship all through the lens of virtue.

Nonetheless, I agree with Fossheim that there can be more material here. One wants  practical frameworks for becoming and practicing virtue. Fossheim gestures at a useful framework that I'll talk about here, strategies or implementation intentions.

First consider the following story:

Nora is concierge at a hotel. Every day, she helps guests—making reservations, hailing taxis, getting luggage into and out of the rooms. Now and then, she is met with rudeness. On such occasions, she is generally taken aback, and often does not even really see what is going on until the episode is over and it is too late to decide on an appropriate response. Looking back on them, she experiences such situations as degrading, and feels terrible about her own lack of command of them.

What should Nora do? She knows that she doesn't want to burst into anger -- her job is important to her. But it is  important to that her that she not feel degraded and get some control over the situation. Fossheim continues the story:  On the advice of a friend, Nora breaks one of the common sorts of situation into more basic elements, and comes up with the following rule: “Whenever a guest gives you a blunt order instead of asking you for help with their luggage, do what they demand, but without a smile or any other civilities.”

What Nora and her friend do is come up with a strategy. Nora can now go forth with her new strategy and apply it to her life. With strategies like this we can become more virtuous.

A strategy, like implementation intentions, have the form of "if-then" plan. Nora's implementation intention is: If a guest is rude to Nora when she is working, then she will help but without any civilities. Here is the upshot, when you are thinking about how to be more virtuous come up with implementation intentions. In what situations do you want to be virtuous? What will you do to show your virtue?

During journaling and other reflective episodes, stop and ask yourself what new behaviors you'd like to start. Be specific and precise. And then practice. You may not get the behavior right at first. Perhaps Nora will find that if she continues to smile that she can take control over the situation. Perhaps some guests will call for different responses.

Let's end with a reminder from Aristotle:  

The aim of studies about action, as we say, is surely not to study and know about each thing, but rather to act on our knowledge. Hence knowing about virtue is not enough, but we must also try to possess and exercise virtue, or become good in any other way.