Gravel sub base

[Shazad.m.]

Hi All, currently trying to build a shed base/ paved area at rear of garden. Total area for the slabs is 5.4 sq m. I have dug down 11cm and started to now fill this with about 5cm coverage sub base which I made myself out of gravel ; bits of concrete and dry soil. However I have not got a hand tamper or a whacking plate. Is there any old school methods you can suggest ? I've been stepping on it and jumping on it a step at a time but obviously this is no substitute.
Also what is best for this type of base? Screed or sand/cement ? The slabs are the standard grey 60x60 depth 25 mm.

 

[blup]

A garden roller , or one of these:
https://www.wickes.co.uk/Wickes-Steel-Professional-Contractors-Rammer---1-245m/p/186866

Blup