Add sugar and salt. Continue over medium heat, stirring constantly until all the sugar is melted.
Be careful not to let it boil (it can burn quickly) and make sure every chunk of sugar is melted. Turn down the heat if necessary.
Coat the seeds with the sauce and spread onto a parchment lined pan to cool. Pressing with a fork works nicely, but work quickly. The sugar hardens fairly quickly.
Allow to cool completely. The seeds should break up nicely with your hands, but will still be in chunks, stuck together.
Notes
Store in an airtight container for a couple weeks.
Make sure you have everything prepared before starting. Prepare a pan, measure all ingredients, have a fork out. You need to work very quickly so that it doesn't harden before you are ready.