Persuasive technologies drive behavioral changes across domains like healthcare, education, and e-commerce but face ethical challenges around consent, autonomy, privacy, and transparency. This study explores ethical design considerations in Human-Computer Interaction through expert focus groups and interviews. The study provides guidelines for the design of ethical and trustworthy persuasive technology. Key findings highlight the need for clear consent mechanisms, visual aids to reduce consent fatigue, customizable notifications to enhance autonomy, and transparent communication with algorithmic clarity. Participants also emphasized the importance of mechanisms for rectifying user errors and promoting equitable navigation. These insights offer practical guidance for fostering trust and ethical engagement, with future research needed to explore diverse demographics and long-term effectiveness.