Vocabulary grows the same way most skills do: through repeated, spaced contact, not through one long read-through of a word list. The methods below are the ones that hold up, without promising a shortcut that doesn't exist.
Read slightly above your level
A book, article or set of instructions that's a little harder than what feels comfortable puts new words in front of you surrounded by context. If you meet the word ubiquitous in a sentence about phones being everywhere, the surrounding sentence does half the work of teaching you what it means. A dictionary definition alone rarely sticks as well.
Keep a small word journal
Write down words you meet and don't fully know, along with the sentence you found them in. The act of writing it down, not just highlighting it, is what makes it more likely to come back to you later. Keep the list short enough that you'll actually reopen it.
Space out your review
Seeing a new word once teaches you almost nothing that lasts. Seeing it again a day later, then a few days after that, then a week later, is what moves it from short-term memory into long-term memory. Flashcard apps built around spaced repetition, like Anki, automate that schedule so you're not guessing when to review.
Use the word, don't just recognize it
Recognizing a word when you read it is a lower bar than being able to use it correctly in a sentence of your own. After learning a new word, try to use it out loud or in writing within the next day or two. A word you've used once is far more likely to stay with you than one you've only seen.
Build a small daily habit
Consistency beats intensity here. A few minutes a day, every day, with a short review of words you've met before, outperforms an occasional long study session. That's the same idea behind a daily streak: small and repeated wins over big and rare.
Turn it into a game
Testing yourself is part of what makes new words stick, and a quiz or a matching game does that testing without feeling like homework. Tile Streak's vocabulary quiz and word lists are built around exactly that kind of short, repeatable practice, and the daily word game puts letters and meaning together in one puzzle if you'd rather play than study directly.
Once a technique or two here feels natural, how to memorize vocabulary words goes deeper into the memory side specifically.