Not really secrets.
The short version (maybe useless, but here goes).
Firstly you need a single basket that is capable of actually being tamped - just like my 7g VST (and so few others - sigh). The first two photos are from VSTs website (renamed by me for clarity). BTW, they refer to it as "ridged" - it isn't really in the sense that it doesn't have a slot for a retaining spring like other "ridged" baskets. That means it is not a "shallow saucer shape" (what the ****** were they thinking when they "designed" those - it cannot ever work). It must have a small deep centre with a shelf to connect it to the 58mm p/f holder. Then you can use anything circa 40mm as a tamper to fit it. The coffee grounds never get onto the shelf as it would take around 10g to do that. The third photo is my 316 stainless single prototype (fits a Pullman handle - I prefer them, personal preference only ). Note: The sides of the stainless are tapered to fit the sides of the VST, the shelf matches the VST shelf. Considering I used a 500 / 600ml "Smartwater Lime and Guava" bottle (about 1/3 full of water to balance it somewhat) for over a year I reckon anything that fits properly will do.
VST 7g from top.jpegVST 7g from side.jpegTamperPreSingle.jpg
Secondly, singles are a bit (cough) more finicky in terms of dosing quantity and require a grinder with an even particle spread (specifically: no twin peaks like most conicals). So virtually any good flat burr grinder will do (Mazzer Major, Mahlkoenig Vario gen2+, EK43 etc - FYI, I had no success at all with a Mahlkoenig K30, YMMV).
Thirdly, I use progressive tamping (taught to me in late '79 by a Northern Italian - my own "coined name" for it). Just like the Swift grinder, tamp about 2ml of "fluff" at a time at a very light tamping pressure. FWIW, I use the weight of the tamper plus just enough extra heft to level it. The Swift uses around 8 pounds - nowhere near Schomer's much quoted "30lbs" (apart from totally disagreeing with him on that, I have no idea how he thought it up in the first place).
I have a much longer, full answer if needed. Hopefully this will be enough to get you sorted.
PS: The photos failed first time around. Relinked them.