My approach to the basing is somewhat simpler than Extra Crispy's.
1 ) Paint the pennies. I use cheap craft-store acrylic paints. My current preferred color is "mushroom" (a very dull brown). But chose your own preferred "dirt" color. The detailing of the pennies is not very important (

). Even full coverage is not important. But you do want to get reasonable coverage on the edges. Let dry for about 20 minutes. More if you have something to do. Leave 'em in the sun, even, if it's a nice day. The sunshine bakes the finish nicely and makes it very tough.
2 ) Mix some of the same paint into acrylic gel medium in a tub. Just enough paint to give it the same tint. Don't worry about any residual transparency in the medium.
3 ) Put big globs of the tinted gel medium onto some pennies. I find that 3 or 4 pennies at a time is about the right quantity. Smush it around with a paint brush to reasonably cover the top of each penny.
4 ) Chose the already-painted infantry figures you plan to base on a penny. Push them down into the glob of gel medium on the penny. Use a small (not micro-fine, just small) paintbrush to dab a bit of the gel medium onto the top of the molded-on figure bases between and around the figures' feet (or their bodies if prone). Do this with all 3 or 4 stands.
5 ) Dribble some sand / ballast, and some small RR shrubbery, around the figures on the pennies. Then bury the pennies in flocking. Yep, just pour a bunch of flocking on top until they are buried. Leave them for about half an hour (while you do 3 or 4 other sets of 3 or 4 stands).
6 ) Gently pick up the stands and tap them on their sides. The excess flocking will fall off. Collect this excess to be re-used for later sets of stands. Use a clean dry paintbrush to wipe any residual flocking off of the figures on the stand.
7 ) After another hour or so of drying time, spray with dullcote.
In about 2 1/2 to 3 hours I can base a company of infantry.
If you don't know what acrylic medium is, it's the stuff that acrylic paints are made from. Basically it is un-tinted paint. If you get gel medium, it will have the texture of pudding. Much easier to work with than white glue, and it has excellent adhesion (you can buy acrylic glues too ... same stuff, different label. If you buy it as gel medium you get A LOT more for your money). So you are using one product that can provide both the texture/depth and the adhesion you want on your stand. And it holds color as well as the paint you are using, which is, after all, the same stuff!
So the acrylic gel medium will hold the figures onto the base, give texture to the base, provide the color to the base, and hold the shrubbery and flocking onto the base, all in one.
And one great advantage of using pennies is that I never find I am just a few bases short of completing my project. I can always find a few more pennies between the sofa cushions if need be.
Works for me.