You can try do trading but you need more knowledge before before start trading ,  trading its risky also but you can prevent this by doing research before buying altcoin so you can know who coin have potential to increase. You can earn bitcoin weekly if you do that but you need more capital in trading to earn good amount. You dont invest in hyip or ponzi because all of this are scam the founder run after few hours and few days only and your bitcoin gone if you choose that yes other people earn bitcoin in hyip is very less compared to the people lost their bitcoin because of this.