1. Update WordPress to the latest version, if you don't know how to do so, click here to update now.
2. Update all your WordPress plugins, newer versions are known to fix bugs that were in the previous version and can go along way in helping you. It is best practice to use stable versions of plugins, (Alpha and Beta versions of plugins should not be considered)
3. Update your WorldPress Theme files, many of the premium theme vendors allows of upgrade when you purchase their products, once you have an update, perform it. Never go for nulled or cracked WorldPress Themes.
4. Reduce plugins; do you really need all the plugins you have installed on your site? Think about it and make critical changes. When I had my first WordPress site, I had 87 plugins installed, but after I was hit with the hammer of my host, I realized that most of the plugins were actually not for me, I quickly ran a scale of preference and ended up with 20 plugins. My site ran faster and was more simple. They are alot of things that can be done within the theme files and requires no plugins. Before ever thinking of installing a plugin, try as much as possible to confirm if you can manually add the feature you want by adding a simple line of codes to your template files. Another reason why step 1 of this tutorial is very important, sometimes the features of one plugins might come with a recent WordPress update and as such making the plugins unnecessary.
5. Only activate plugins when you need them, if their use becomes automatically redundant, quickly de-activate. For example, you don't need to have WP database backup plug-in if you are not auto scheduling a backup, and so

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