Have you made any progress London? The posts here should have directed you to learn from Rhodium's site about extractions. If not, here is some general technique as a starting trial for your extraction. It is micro-scale so you can try it a few times without fucking stuff up. Measurements are not tested and thus not precise, they are only a starting point. Only experimentation will tell how much of everything. Feel free to ask questions, if the search engine doesn't answer them. This is also minimal on equipment. This is just how I would get started:
Place 5g of pulverized wormwood (or sage I guess) in a 50-mL rbf with a few boiling stones and add 20mL diethyl ether (or try another solvent, such as dcm). Attach a condenser and reflux for 45-60 min. U probably don't have a hot plate, but don't use an open flame. Cover your stove top with metal - u can buy large stove covers that Orthodox Jews use due to Sabbath consideration; or more ghetto, cover the flame with a metal pan (in this case use something less flammable han ether). Then let everything cool for a short period of time (go have a cigarette). Filter your product paper as well as you can (wich may just mean doubled up coffee filters a few times. Collect in another small flask. Rinse out the first flask with a few mL of solvent and filter that. Remove the solvent by simple distillatinon of the product mixture on the same hotplate/pan/etc. u used before.
Dissolve the oil you have left over in acetone while heating via hot-water bath. Pour the dissolved solution into a third flask and let it cool at room temperature (this is to keep it pure, read the sticky threads in the newbee forum). After all the moisture looks like it's gone, leave your product out to dry on coffee filter paper, to absorb any leftover humidity.
Make sure to do this in a well-ventilated area with proper safety procedures. Do not pour your diethyl ether down the drain.
Post note: if you can't set up proper ventilation, don't use diethyl ether. In fact, 95% ethanol grain alcohol should work for thujone. If you can find out thujone's boiling point (Merck Index), then this should work much better. You should find a place that has diagrams of reflux and distillation set-ups such as Rhodium's site or, better, a chembook from a used book store. You may also be able to cut out the reflux step if the boiling point is low enough and you have a hot plate or can set up an oil bath. Alternately, a vaccum could be used to lower the pressure.
I myself am a newbee, so maybe someone can help out here.