php error in page/post editor after activating soccer info plugin

I get two php errors below when going to ‘Pages -> Add New’ or ‘Posts -> Add New’ in the dashboard:

Strict standards: call_user_func_array() expects parameter 1 to be a valid callback, non-static method SoccerInfo_Admin::add_editor_plugin() should not be called statically in C:\wamp\www\psgthing2\wp-includes\class-wp-hook.php on line 298
Call Stack
# Time Memory Function Location
1 0.0006 266792 {main}( ) ..\post-new.php:0
2 0.7267 39129088 include( ‘C:\wamp\www\psgthing2\wp-admin\edit-form-advanced.php’ ) ..\post-new.php:85
3 0.8618 40229160 wp_editor( ) ..\edit-form-advanced.php:633
4 0.8634 40548688 _WP_Editors::editor( ) ..\general-template.php:3056
5 0.8644 40555392 _WP_Editors::editor_settings( ) ..\class-wp-editor.php:294
6 0.8677 40624560 apply_filters( ) ..\class-wp-editor.php:399
7 0.8677 40625056 WP_Hook->apply_filters( ) ..\plugin.php:203
8 0.8678 40626192 call_user_func_array:{C:\wamp\www\psgthing2\wp-includes\class-wp-hook.php:298} ( ) ..\class-wp-hook.php:298

( ! ) Strict standards: call_user_func_array() expects parameter 1 to be a valid callback, non-static method SoccerInfo_Admin::register_editor_button() should not be called statically in C:\wamp\www\psgthing2\wp-includes\class-wp-hook.php on line 300
Call Stack
# Time Memory Function Location
1 0.0006 266792 {main}( ) ..\post-new.php:0
2 0.7267 39129088 include( ‘C:\wamp\www\psgthing2\wp-admin\edit-form-advanced.php’ ) ..\post-new.php:85
3 0.8618 40229160 wp_editor( ) ..\edit-form-advanced.php:633
4 0.8634 40548688 _WP_Editors::editor( ) ..\general-template.php:3056
5 0.8644 40555392 _WP_Editors::editor_settings( ) ..\class-wp-editor.php:294
6 0.8716 40637952 apply_filters( ) ..\class-wp-editor.php:632
7 0.8716 40639952 WP_Hook->apply_filters( ) ..\plugin.php:203
8 0.8716 40641456 call_user_func_array:{C:\wamp\www\psgthing2\wp-includes\class-wp-hook.php:300} ( ) ..\class-wp-hook.php:300

Could you please help me to sort this error out?