Remove PHP closing tag from end of file
Remove unused function twentyten_admin_header_style()
Remove unused function twentyten_posted_in()
Remove unused function twentyten_get_gallery_images()
Remove redundant code

The proper way to remove the WP Version from the header is
“remove_action( ‘wp_head’, ‘wp_generator’ );”, which is found below.
Adjust whitespace and code styling
Fix the function that is filtering the admin footer

When using WordPress filters, the proper method is to return the
filtered value rather than echoing the new value. We need to allow
WordPress to appropriately act on the filtered value, instead of
hijacking what WordPress is doing.
Remove unused post-format code
Update the theme text domain for translation
Include the text domain for the __() function
Update spacing, and include text domain with __() function
Use the 'wp_enqueue_scripts' hook to properly include the stylesheets into the theme
Include text domain strings
Use get_stylesheet_directory_uri() instead of get_template_directory_uri()

The get_template_directory_uri() function refers to a parent theme, if
there is one.
Adjust code spacing
Check to ensure the get_field() function exists

Because the get_field() function is part of a plugin, it is good
practice to ensure the function exists before attempting to use it, in
case the plugin is not active.
Only call the get_field() function once for each field

It looks like the get_field() function is pretty responsible in calling
the database, but it’s still helpful to limit the potential calls to
the database when possible
Adjust spacing for readability
Use get_sidebar() function instead of include()
Fix some formatting for readability