Open Play Store and head over to Settings.
Tap on Auto-update apps.
Choose Do not auto-update apps.
If you want to enable the auto updates, follow the same path and choose Auto-update apps at any time or via Wi-Fi (available for certain Android devices only).
To update your apps manually, just open Play Store, and on the main page swipe in from the left and tap on My apps. You can tap on apps with pending updates and update them manually, or if you like to update them all at once, just tap on Update All.