The words by and itself are common words in the English language, but they can often be replaced with synonyms that add more depth and nuance to your writing. Here are some alternatives for the word by: via, with the aid of, through, using, by means of, and by way of. Each of these words can change the tone or focus of your sentence in a subtle way. Similarly, here are some synonyms for the word itself: intrinsic, inherent, innate, essential, and integral. Using these words can describe the nature or identity of something more accurately than the word "itself" alone. Expanding your vocabulary can bring variety and nuance to your writing-- try experimenting with these synonyms for by and itself in your next assignment or email.