It's easy: Start with the KISS formula:
Keep it stupid simple.
Basically in every miniature game, fighters have at least one of the following three roles:
The melee dude, who likes to take the fight as close as possible.
The ranged dude, who likes to shoot.
The supporting dude, who does not exactly fight but rater uses his abilities to support the others.
Of course, combinations of these three archetypes are possible, too.
But for the moment let's focus on these three.
Because all you need now, are Icons - or rather: graphics - representing these roles:
A sword can mark the melee dude, a bow is a symbol for the ranged dude and a wand can classify the supporter:
Find some graphics, print them out and Stick them to some meeples - voilá, your own miniature!
Ok, the shield here stands for "extra armour", but as you can see: anyone can be anything! It's up to you to create your own fighters and to unleash them on your enemy!
You need a game to play with those?
How about a nice game of Whack & Slaughter :)