Some definately began in straight Dunkelgelb - there's footage of Hitler inspecting a new batch that are clearly only in DG. If a vehicle survived long enough to get re-painted then simpler schemes appeared (here's a couple).
It doesn't have to be a challenge to produce a basic camo, all you need are some rattlecans in the three basic colours, (Dunkelgelb, Rotbaun or Schockobraun & Olivegrun or Resedegrun) Tamiya do decent versions & some blu-tak.
First put down a coat of the DG (& make sure its dry before moving to the next step - at least a couple of hours & preferably longer). Then, with reference to a scheme you like, apply the blu-tak (this will protect the DG pattern). Then spray the OG/RG - let dry, add more blu-tak & repeat for the RB/SB.
you could then give a light dry brush to the different colours (Vallejo Model colours provide all you'd need) & wash to taste.
Hope that might be of some use