Make sure you wear your binding necklace so you have a 100% chance of making all 5 steam runes. The fastest way to craft the steam runes is to run north-west of the Duel Arena and enter the Fire Altar. Use the fire talisman on the Mysterious ruins to enter, and then craft the desired number of steam runes by using the water talisman on the Fire Altar. Once you have crafted the steam runes, you must take them back to Wizard Dougal for approval before giving them to Clerval.