Both dfx and trunk commands occupy the console while running, so you'll need to use separate terminal windows for each.
First, in one terminal, start the local PocketIC:
dfx start
Then, in a second terminal, deploy your canisters and start the Trunk development server:
make deploy
trunk serve
./tailwindcss -i ./crates/frontend/src/input.css -o ./crates/frontend/css/output.css --watch