Several small adjustments in OS X Yosemite can improve the speed at which your Mac operates. If these procedures don't sufficiently speed up your computer, upgrade its RAM and drive.
In OS X Yosemite, a new feature makes menus and folders transparent. Although it's nice to look at, this small feature can slow down your Mac, particularly if it's an older computer. To disable this feature, click the "Apple" menu in the top corner of your screen and select "System Preferences." Choose "Accessibility," select "Display" and place a check mark in the "Reduce Transparency" check box.
Changing the Minimizing Effect
When you minimize a window on a Mac, the computer uses a fancy little effect to make the minimizing process more interesting to watch. Although it's a small thing, changing this effect can improve the snappiness of your Mac. Select "System Preferences" on the Apple menu and click "Dock." Click the "Minimize Windows Using" drop-down menu and select "Scale Effect" to set scaling as the minimizing effect.
Monitoring Programs and Processes in Activity Monitor
The Activity Monitor application on your Mac indicates which programs and processes are running on your computer and how much of your system resources they're using. If a process or program is using a lot of system resources, it slows down the overall operation of your computer. Press "Command-Spacebar," enter "Activity Monitor" in the Spotlight search field and press "Enter" to open Activity Monitor. Locate the column labeled "CPU." Look for processes and programs that are using a large percentage of processing power. If you find one you don't need running, select it and click the "Force Quit" button at the top of the Activity Monitor. The Force Quit button looks like a stop sign with an X superimposed on it.
Disabling Unused Widgets and Extensions
The Notification Center in OS X Yosemite is a handy feature you can use to check the weather, monitor your calendar and stay on top of reminders. If you're not using any of these widgets and extensions in Notification Center, disable them; they can slow down your computer. Click the "Apple" menu, select "System Preferences" and choose "Extensions." Click "Today" on the left of the window and uncheck any items you don't use.
Adding More RAM or a Faster Drive
Perhaps the most effective way to improve the speed of your Mac is to increase the amount of RAM in it. RAM is the memory your computer uses to perform actions quickly. The more of it you have, the quicker your Mac performs tasks. Adding more RAM to your Mac involves opening the computer and should be done only by someone who is familiar with the process. Installing a new, faster drive can also improve the speed of your Mac. A professional should do this involved process, as it can result it data loss if done incorrectly.