Try a J.K Rowling approach. Instead of using her first and last name she used her first two initials and her last name. Same with C.S Lewis. J.R.R Tolkein. There's many ways you can make a pen name. The initials of the first and middle name followed by your last name. Use your middle name and your last name. Or use a name, or initial, of someone who you're thankful to for inspiration or support. The person who taught you almost everything about writing, whatever. Your pen name itself could be a dedication.