How to make your fps in minecraft be higher on multiplayer servers?

1: Get better internet
2: Install Optifine (currently not for 1.8)
3: Dedicate more RAM to minecraft

Other than those options there isn't really anything else, it does depend on the server you're connecting to. If it is a big server then they tend to have both EU and US server so make sure you're connecting to the one closest to you.