The best clickthrough parameters for an affiliate program are all about keeping things simple and easy to track. Use stuff like utm_source, utm_medium, and utm_campaign so you know where your clicks are coming from. Keep your links neat and not too long—tools like Bitly can help with that. Make sure your links work well on phones, load fast, and use HTTPS so people feel safe clicking. Adding clear and catchy phrases in your links can also get more clicks. Don't use sketchy redirects or confusing URLs—that just turns people off. Also, use unique IDs for each affiliate to track sales right. Check your data often and tweak stuff to get better results!