Make sure to always mark your long syllables in some way: macrons are the most common (āēīōū), but there's no reason not to settle for apices (áéíóú), circumflexes (âêîôû), or any other marking system! Also pay attention to vowel length when speaking, and try to check if you're not sure!
This will help you learn the rhythm of different words, and you'll future self will thank you when you try to write or read Latin poetry!
#2. Try to use Latin casually from time to time
Lingua latīna fortē mortua est, sed latīnitās valdē vīvit. It's a common mistake to assume that just because Latin is an ancient language, it can't be used for everyday stuff. That's not true though!
With a little help from sources like Neo Latin Lexicon, you have the means to refer to almost any object of daily use. Use this power for learning: journaling or writing down reminders/post-it notes in Latin can be a fun way to keep the language alive in your head!
#3. Use analysis as a tool
Now, I'm far from a proponent of relying on analysing grammar or translating text. That's a great way to spend your time learning nothing (except how to turn the pages of your dictionary more efficiently). But when you're struggling with a text, going through the grammar a bit at a time can give you insight to work off of.
Analysing the grammar in the first few pages of a book can take you m to a point where you can read it fluently - and the best part is, someone's probably done the analysis for you already! Youtube is full of videos ready to guide you through famous classical works.
#4. Revisit your old study materials
This one applies to everyone, but especially LLPSI users: take the time to open your old book once in a while.
You'll find words that you've forgotten, grammar you haven't seen in a while, maybe even expressions you've been trying to find!
Latin grammar and style is rich like very few European languages. And at over 40 000 words, Latin vocabulary is incredibly extensive for a “dead” language - wordier than some languages with millions of native speakers. This means you'll never remember all that you've learnt, often not even all that you need to remember, and returning even to the most basic stuff is worth it.
#5. Talk to Latin speakers in Latin!
I'll be the first to admit that the Latin-speaking community can be weird and daunting. Some people seem to be a bit too into the whole "ancient was better" stuff, which uhh, yikes.
But it's still a really welcoming community that's willing to help anyone capable of minding their manners. The Latin Discord server is the best place to be to practise: you can talk in beginner Latin channels, you can watch advanced speakers in the advanced Latin channels, you might even catch a group lesson, or a classics micro-celebrity appear in!