Create a theme directory

Go to /app/design/frontend

1.Declare your theme


<?xml version="1.0" encoding="UTF-8"?>
<theme xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Config/etc/theme.xsd">
     <title>My First Theme</title> <!-- your theme's name -->
     <parent>Magento/blank</parent> <!-- the parent theme, in case your theme inherits from an existing theme -->
     <media>
         <preview_image>media/preview.jpg</preview_image> <!-- the path to your theme's preview image -->
     </media>
 </theme>

2.Add registration.php

<?php
/**
 * Copyright © 2015 Magento. All rights reserved.
 * See COPYING.txt for license details.
 */
\Magento\Framework\Component\ComponentRegistrar::register(
    \Magento\Framework\Component\ComponentRegistrar::THEME,
    'frontend/stark/my-first-theme',
    __DIR__
);

Magento 2 Index Management

|| Magento2 reindex on local server

You can’t reindex from admin web. you have to reindex from command line

  1. go to command line from magento2 installation root directory

  2. php bin/magento indexer:reindex

if you got any error like ‘php’ is not recognized as an internal or external command,

so you need to Add E:\xampp\php to your PATH Environment Variable.

final command:
E:\xampp\htdocs\magento2>php bin/magento indexer:reindex