1.Font!
http://www.diyiziti.com
Directions:First ,according to the style of power point,you should choose the type of fonts. Then you can set the size and color. Finally youc an save it as the form of transparent png and put it into the PPT.
2.Icon!
1)http://www.iconfont.cn/
Directions: The website is very famous and you can search what you need then download them directly.
2)http://www.easyicon.net
Directions:This website updates the icons every day especially the style of UI and drawing. However,you must use the English as the keyword.
3.Pictures
Directions:This website is for free and pictures in this website are all beautiful . But if you were not a VIP you just can download some pictures. Ps:There is no restrictions for VIPS
1)http://www.hituyu.com/
2)http://699pic.com/
3)https://www.pexels.com/
Directions:All the pics in this website are for free ,but you can only search key words in English. In this website, you can choose the size of pictures you want, and it's very convenient .
4. Templates
1)http://www.ppt20.com/
In this website, If you want these high-quality templates, you need to pay money. And you will not feel regretful because templates in it are amazing!
2)http://www.pptstore.net/
This is an old top and original template website,and it has become one of the most popular websites in China for a very long time. In a word, high quality high price.