I believe that if you read on in Section 3 you will find broad (broad enough) exceptions to guide you through the firearm transfer process should you be an unlicensed dealer. There are for example exceptions for gift transfers to family members, antique firearms, and to minors for hunting, among others. Simple use of a buddy's firearm at a range or while hunting does not appear to be materially impeded. The law seeks to prevent transfers to felons. There are requirements and consequences if you transfer firearms to felons. To non-felons, not so much. When in doubt, the law provides for use of a licensed dealer to perform a background check before a transfer takes place. As with the US Constitution generally, consider reading the entire law in context.

Disclaimer: gun owner, NRA member who voted in Favor of I-594