CSS Tips

I've noticed some people having issues with their css coding. To be honest the easiest way to code is to take someone else's coding layout and paste it into your css box from there you can change the url links to be the images of what you want, you can change the font, the color of the font, borders, etc...What I did was lets say I wanted my page to slide in, I found someones who did that, pasted their layout in a google doc, then found what I thought was the code for the slide in. Pasted it in my css box its important to paste it near whatever they did so this person had their slide in code at the top of their css box so I pasted mine at the top as well. I hope that explained it in a good way. If you need help message me <3