If you haven’t read any of the Stoic litterature I suggest you start with The Practicing Stoic. The book is well structured with chapers on topics like “Wealth and Pleasure” and “Adversity”. Each chapter mixes fragments of the Stoic litterature to give an overview on what the sages said on the topics. This serves as a good introduction to the different sources, so you’re better prepare when you dive into them yourself.
As Ward Farnsworth states in the preface to The Practicing Stoic: “The most productive advice anyone offers nowadays, casually or in a bestseller, often amounts to a restatement or rediscovery of what the Stoics said with more economy, intelligence, and wit, long ago. The reader does better by going straight to the sages.”
After reading that book, you’ll be well-prepared to dive into some of the original Stoic writings. I’d suggest starting with Letters From a Stoic. As the title suggests, this is a collection of letters, 124 to be precise, with titles like “On the Use of Time” and “On Progress,” spanning just a few pages each. This format makes it easy to get started and to immediately benefit from Stoic advice.
For those seeking help with applying Stoic wisdom to their own lives, consider picking up one of the more modern takes on Stoicism, such as Ryan Holiday’s books, starting with The Obstacle Is the Way. His books usually take some small subset of Stoic teachings and elaborate on it with example from modern times. Hearing such examples might be motivation to you. Personally I find the examples distracting.
If Ryan’s books aren’t to your taste, you might enjoy A Guide to the Good Life. William B. Irvine attempts to answer the question: If the ancient Stoics had taken it upon themselves to write a guidebook for twenty-first-century individuals – a book that would tell us how to have a good life – what might that book have looked like?