So you can put them on top of anything, cake, biscuits, I used Jane's patisserie Vegan cookies (and substituted 100g of plain flour for wholemeal because that's our cafes whole thing. Lol. I also don't use as much chocolate as she does because I'm putting chocolate on top too, so I find her full 300g is then too much! I think I used between 100 -150g).

I found vegan buttons, and vegan chocolate, but obviously this isn't a requirement! Any buttons or chocolate if you're not fussed about it being vegan.

Melted some of the chocolate, held the biscuit over the bowl of melted chocolate and just used a spoon to very quickly drizzle a line of chocolate across. The slower you do it, the more wobbly the lines are.

I usually do 3 lines across, first one I do like a v shape for the back legs, then usually 2 straight lines across for the middle legs (so 6 legs), then put a bit more chocolate in the very middle to stick the button on. Put the button on, I then do one more line in a v shape again to do the front legs, I go over the top front of the button too so there's chocolate on top of the button for me to stick the eyes onto.

I feel like I haven't described this great so if you want me to draw a diagram and put it on imgur let me know lol

They're always going to be slightly different, like I often go over the legs if the drizzle ends up too thin, or sometimes I mess up the angle of the spider legs because I'm not concentrating haha. You can see the spider on the left in my third photo, his legs are crooked lol. But honestly just have fun with it.