Hi Vicky, congratulations on your undertaking of the Cert IV program. Im going to attach the link to the TPB which outlines relevant experience requried to become a Registered BAS Agent. If the big picture is for you to own and operate a bookkeeping business and provide BAS services for a fee, BAS Agent registration is mandatory. In answer to your question on clarification on what hands on experience is? - doing bookkeeping services for a business as an employee, or doing bookkeeping under a person or entity that is a Registered BAS or Tax agent who can supervise your work. To be certified, you will also need to change your ICB membership, and I have attached the information here for you also.
Explaining ICB Membership
Bookkeepers Career Path - ICB
Relevant experience for BAS agents | TPB
I hope this has helped.