I have learned from Gandolfi here om APUG that you can use a sponge. It workes fine, bur I suppose Emil/Gandolfi can tell more abort it.
On a wisit to London I bought brusches from Silverprint. They are OK, but smal. For bigger prins I have bought some sheap brusches from a Swidish company called "Biltema". They workes fine. But I suppose you do't have that company in Prague.
I have also locked at the kind of brusches that women uses to put makeup on their cheec.
If you buy theese brusches, You have to cut Themsen with a scistor.
Don't knop if it helps, but this is the only answer I have.