You can attempt whichever you feel comfortable with and post your finished work on the contest page so that it is visible. If you decide to do a process post as well which most people are doing now, then try to include atleast half a dozen photos of your process from start to finish with a brief explanation for each. You don't have to make a process post to enter but it helps others who ae new like yourself see the steps they might take to create the drawing themselves which will hopefully help make things a little less daunting for anyone wanting to give it a go. Some of the process posts have also been quite successful at earning rewards in their own right with a couple even receiving over $100 so there is a bit of a win/win element to the contest whereby if you don't win a prize you will usually get some reward for your process post....Hopefully! :)

I hope that answered your questions and if you have any more I'd be happy to answer them. :)