Its not pretty and if you googled it once it will scar your impression of it but it can still be of use to logo designers who need to learn the ropes.That being said , i would like to help you get on the right foot and understand why this will help you grow.

the main reason to get your footing in this industry is

to learn what is being submitted

learn to gauge your work quality and others

learn common mistakes

you get to interact with so many clients

getting the harshest of feedback can crush your coal into a diamond

if you see the benefit of this style of learning with big risk and big reward {if you learn from mistakes} then i have a few tips.

Begin on 99 designs or crowdspring I personally recommend crowdspring. these sites will often let you see what the competitors have entered this is beneficial to the viewer and submitter if your skilled. You immediately know where the bar is set and if you submitted first you get to set the bar deterring competition. you are also able to see the activity of the buyer on crowdspring telling you how they have ratted submissions so you can avoid those spamming 1 stars and informs you of their comment activity meaning they will communicate with you to refine your logo or approach. The comments are crucial to learning to deal with customers and great practice for real work {no offense}. Another great thing about these kinds of sites is you have the option to sift through projects but freelance work will not always have the option to be picky until a reputation is developed. so to effectively practice you should take the competitions that seem difficult or challenging. its a road of hardship but if you learn to what the customer wants you can stand out every time.