You launch Planck by typing
planck in a terminal.
If you'd like to get help on the command line arguments to Planck, do
The command line arguments to Planck are heavily modeled after the ones available for the Clojure REPL. In particular, you can provide zero or more init-opt arguments, followed by an optional main-opt argument, followed by zero or more arg arguments.
Note that, Planck accepts long arguments (preceeded by two dashes), just like the Clojure REPL, but with Planck there must be an equals sign between the argument name and value, as in