Most improvements in OS X 10:11 El Capitan are not immediately visible to the ordinary OS X user. Especially under the hood many improvements have been made in the area of performance and safety.
Do you want OS X 10:11 El Capitan faster than you can use the OS X Terminal Commands 10 below. The commands disable various delays from that standard built by Apple.
Open OS X Terminal, which you can find in the folder: Applications ▸ Utilities. Copy and paste the following command either in the Terminal window.
OS X user interface
1. Disable animations when opening and closing windows.
defaults write NSGlobalDomain NSAutomaticWindowAnimationsEnabled -bool false
2. Disable animations when opening a Quick Look window.
defaults write -g QLPanelAnimationDuration -float 0
3. Accelerated playback when adjusting the window size (Cocoa applications).
defaults write NSGlobalDomain NSWindowResizeTime -float 0.001
4. Disable animation when opening the Info window in OS X Finder (cmd⌘ + i).
defaults write com.apple.finder DisableAllAnimations -bool true
5. Disable animations when you open an application from the Dock.
defaults write com.apple.dock launchanim -bool false
6. Make all animations faster that are used by Mission Control.
defaults write com.apple.dock expose-animation-duration -float 0.1
7. Disable the delay when you hide the Dock
defaults write com.apple.Dock autohide-delay -float 0
8. Disable the animation when you sending and replying an e-mail
defaults write com.apple.mail DisableReplyAnimations -bool true
defaults write com.apple.mail DisableSendAnimations -bool true
9. Disable the standard delay in rendering a Web page.
defaults write com.apple.Safari WebKitInitialTimedLayoutDelay 0.25
10. The keyboard react faster to keystrokes (not equally useful for everyone
defaults write NSGlobalDomain KeyRepeat -int 0
When the commands are conducted in OS X Terminal, you need to reboot your Mac. After re-login you will notice that your Mac responds smoother.
If you want any of the above commands undo than is possible using the defaults delete command.
defaults delete domain key
Example: To undo the adjustment number 10, type the command:
defaults delete NSGlobalDomain KeyRepeat
After undoing, you need to restart your Mac.