First, let me say that I use all of the following figures in my dioramas, mainly to get a larger variety of poses.  The vehicles, tanks, made by different companies are a little more difficult to integrate into the same diorama unless you are using just one of a certain vehicle or tank.   The following is a list of the names of some of the companies that I use : Airfix, Revell, Pegasus, Esci, Caesars, Hat, Atlantic, Matchbox, Fujimi, Hasegawa, Italeri, Imex. Eko, Roco, and Roskopf. Bare in mind that these all have different properties in their plastic and require varied levels of effort to prepare for your battle scene.  In general , preparation requires that they be debased.  This can easily be done using an Exacto knife, or Dremel. Next, the mold parting lines should be trimmed all around the figure, but please keep in mind that the hardness of the plastic is a good indicater of the task you have ahead. You may want to use a mini file to accomplish this .Also be sure to remove the (chatter), those small shards of plastic that do not come off.  The use of a lighter can be helpful, passed quickly over the area where there is excess plastic.  You do need to be careful not to get too close to thin pieces such as weapons, shovel handles, hands, and thin arms. Once you have trimmed the figure, you may want to give them a quick wash with some detergent to remove the oils, etc.  After they have thoroughly dried, you can apply a coat of primer which is compatible with the type of paint you are using.  After the primer has dried, is a good time to check the figures for areas where there are places you may have missed trimming. Next, you can begin painting the figure.  You really only need two brushes one must be very small for the fine detail such as equipment, chin straps,flesh,piping, badges of rank, etc.  You can cut down a small brush to a desired thickness.  The larger brush can be used for the basic color of the uniform. I recommend working your way out on the figures.  By this, I mean paint the uniform first, then the belt, pack straps, equipment, and finishing with the really fine detail such as piping, chin straps, and badges of rank. Of course this planning is up to you.  You may also use a small Berol pencil to do alot of the fine detail. Finally, you may want to use some dullcote to protect the finish. Usually, the armor and other vehicles can be done in the same process as the figures.One rule I have is that if you handle the figures too much, plan on repainting them.  I usually try to plan where to place the figure, touch the feet with some white glue and then place it.  Try to have some type of brace on hand to hold the figure to the desired angle until the glue dries. Of course, there are many areas which I have not covered and I hope to add to this guide in the future.This is just my way based on forty years of contact with this hobby.  Soon, I hope to add another section on weathering.