Yes, I love writing articles on crucial subjects.
There are two "usual" ways of drilling holes in fimo beads : before or after baking (what a surprise, I know). The "before" method requires less equipment than the "after" one.
Making holes in fimo beads before baking:
You may use a needle or a toothpick, this is very simple. However you have to be very careful as your polymer clay is still unhardened. The best thing to do before drilling is to put your raw beads in the fridge (or at least stop manipulating them). Let them a few time to be sure they are cold enough to be handled without being too easily destorded. When drilling the hole, gently rotate the bead around the needle. Be careful with "old" clay, it may be a bit dry and crack easily.
Instead of a needle or a toothpick, depending on the size of the hole you want to drill, you may use a very small round cookie cutter. For example to drill holes in my donuts (not the hole in the middle, it would be a little too easy! No, the hole to put the cable or ribbon) I use the little ink tube of a Bic pen. This is far from being a very professional cookie cutter but... it works! For my hole to be clean, I put plastic film on the fimo donut before drilling.
So... drilling holes in fimo beads before baking is very simple. And it offers the possibility of baking your beads on a rack, what's really handy. However this method may not be convenient with very small or thin pieces, easily distordable when raw... you have to choose our second option.
Making holes in fimo beads after baking:
This is when, in my case, it becomes very spectacular (or only a little, maybe).
Our fimo beads are hard, we need a drill. A Dremel tool is the most suitable for polymer clay. Unfortunately I don't have the tools of a professional beads maker, I have the tools of a professional... (herm don't know, carpenter maybe...). So I've got this :
(Yes, it is about 80 centimeters high)
However the main point is not the size of the drill itself but the size of the drill bits we use with it. The smallest I use are 1mm. They are small and consequently easily breakable... be gentle when pushing them into the bead.
Let the polymer clay fragments go out from the bead, pulling up (without taking it out) the drill bit from time to time. Use a drill vice to hold the bead (and nooooot your fingers, of course). When the drilling is almost done, this is the moment when the extremity of your fimo bead is likely to crack if you're not careful. Don't go too fast!
Drilling holes with a real drill takes equipment and a little of know-how but is still very simple. An important thing to know : don't try to drill holes into cold fimo beads with this method (for example if your drill is in your garage which is not heated, this is very tempting to store your beads "to be drilled" in this garage, but this is a very bad idea! Cold beads are far more likely to be broken!).
If the bead you want to drill is really too thin... In this case, what I usually do is drilling a first hole, very small and without even going through the whole bead, before baking (with the smallest needle I've got) and enlarging this hole after baking. With a small drill bit (manually, you just have to stuck a drill bit on something you can easily handle and rotate!).