Be very very careful with the router when doing small bases.
I prefer to use it handheld but I use a big extension which you can see on the left of the second picture.
When routing the decorative edge, the extension part stays on a piece of wood which has the same thickness as the base. So one hand on the knobs of the extension part and the other one on the router and here we go. This way, my router is very stable and will not tilt or anything.
You can use it also upside down on a routing table. Well I have a dedicated router and table for that but be extremely careful when routing small parts. Do not put your fingers there. My fingers are always at least a foot if not two away from the router when table routing but, as I said, I prefer to do it without a table since my hand and fingers are shielded by the router plate and its extension. I also wear full face mask and apron when routing and I remove all rings from my fingers and no loose clothing either.
And the best advice I have is respect the machines and repeat in your head what you are going to do before actually doing the routing.