Clip on Hair extension help!!!!

So, I've been searching around the internet to find a way to blend in curly or wavy hair extension with naturally straight hair.I can't find any answer.The case is, I have a naturally straight hair (chest length) and I bought a curly and wavy hair extension (the was a buy 1 get 1 free promo sooo yeah I have two of them now).
Does any of you guys have any tips or ideas on how to make them blend in or at least look natural?By the way, the hair extension I bought was "Shizuka Hair Clip extension"
Please help me out, I would not want them to go to waste :'(

is it real hair or fake hair?