Because Megaminx moves are not standard 3x3 notation (R++, D--, etc.), a great PDF includes a legend. Look for a guide that uses the or a clearly mapped variant.
Moving from a beginner to an advanced Megaminx solver is a journey of unlearning inefficiency. While hardware improvements help (a magnetic YJ YuHu or a DaYan Megaminx feels great), the true bottleneck is always method.