Create cms block in your admin area to manage header contact number, welcome text, social media url, sidebar content or footer text.
You can create textfield, textarea or wp-editor in admin panel easily. Textarea and wp-editor support html content. WYSIWYG editor will give you flexibility to manage content. You will get all blocks shortcodes at admin panel. Use it where you want. Optionally you can use template tag to get all blocks in an associate array.