Fasten the drip edge that addresses the fascia to the eaves. The entire size on the fascia is probably not properly straight, so don’t snap a line; just keep the drip edge snugly against the fascia and fasten it with the prime into your decking with roofing nails. Professional suggestion: https://andredhkor.wikinstructions.com/812113/canadian_technology_news_can_be_fun_for_anyone