Reddit mentions of Stoicism: A Very Short Introduction (Very Short Introductions)

Here is my short list of books that I usually recommend as starting points (most of these are found in the FAQ as well):

• Stoicism by John Sellars is an introductory-level academic overview of Stoic philosophy and is a solid introduction to the subject.
  
  
• Stoicism: A Very Short Introduction by Brad Inwood is another broad overview by an academic scholar of Stoicism, but it's much more condensed. Very informative, however.
  
  
• Stoicism and the Art of Happiness by Donald Robertson is a practical introduction on what Stoicism is and how to implement it in your life.
  
  
• Epictetus - Discourses, Fragments, Handbook translated by Robin Hard is a book containing the lectures of the Stoic teacher Epictetus. He was the most influential Stoic philosopher of his age, and his Discourses were studied by the famous Roman emperor and Stoic philosopher Marcus Aurelius. (The "Enchiridion" is included in this collection as well, also called the "Handbook".)
  
  
• Seneca's Dialogues and Essays, especially the essays "On The Shortness of Life" and "On the Happy Life" and Letters from a Stoic contain Seneca's useful writings on a number of topics and is another popular place to begin learning about Stoicism.
  
  You can also check out the IEP entries on Stoicism and Stoic Ethics if you'd like to start with briefer reading first.
  
  Finally, there are a number of videos on Stoicism and related topics that you may find helpful. (But of course books go into more depth than short videos can.)

Familiarize yourself with the 3 disciplines of Stoicism, eg here. This cannot be overstated, as understanding them helps prevent 90+ % of the common misunderstandings of Stoicism.
If you feel like your background on Stoicism is lacking, I recommend reading Stoicism, A Very Short Introduction by Brad Inwood, which does a wonderful job of portraying Stoicism as a whole.

If you have not already I would recommend reading the Enchiridion daily, until you can recite it almost completely by heart. Play around with the ideas and try to apply them to concrete situations in your life, try to find multiple examples per entry.
Particularly try to apply the dichotomy of control to everything. Start asking yourself constantly if what you see/experience might just be a semblance, a wrong impression. Start being consciously aware of your thoughts. I feel that journaling, helped a lot with this.
I also recommend reading On application of philosophy, and other insightful posts by u/cleomedes.