How to Create Attribute Set in Magento 2 Programmatically?

While product attribute is an individual characteristic of a product, product attribute set is a group of those characteristics that define a product. You will use product attributes every time when creating products in Magento. 

If you need to create multiple product attributes, doing this via the admin panel might require a lot of time. So in case, you need to do it fast, create an attribute set in Magento 2 programmatically. 

Use the following code to create an attribute set programmatically. Create the InstallData.php file in the app/code/Vendor/Module/Setup/InstallData.php.

<?php
namespace Vendor\Extension\Setup;

use Magento\Framework\Setup\InstallDataInterface;
use Magento\Framework\Setup\ModuleContextInterface;
use Magento\Framework\Setup\ModuleDataSetupInterface;
use Magento\Catalog\Setup\CategorySetupFactory;
use Magento\Eav\Model\Entity\Attribute\SetFactory as AttributeSetFactory;

class InstallData implements InstallDataInterface
{
    private $attributeSetFactory;
    private $attributeSet;
    private $categorySetupFactory;

    public function __construct(AttributeSetFactory $attributeSetFactory, CategorySetupFactory $categorySetupFactory )
        {
            $this->attributeSetFactory = $attributeSetFactory;
            $this->categorySetupFactory = $categorySetupFactory;
        }

public function install(ModuleDataSetupInterface $setup, ModuleContextInterface $context)
{
        $setup->startSetup();
        $categorySetup = $this->categorySetupFactory->create(['setup' => $setup]);

        $attributeSet = $this->attributeSetFactory->create();
        $entityTypeId = $categorySetup->getEntityTypeId(\Magento\Catalog\Model\Product::ENTITY);
        $attributeSetId = $categorySetup->getDefaultAttributeSetId($entityTypeId);
        $data = [
            'attribute_set_name' => 'MyCustomAttribute',
            'entity_type_id' => $entityTypeId,
            'sort_order' => 200,
        ];
        $attributeSet->setData($data);
        $attributeSet->validate();
        $attributeSet->save();
        $attributeSet->initFromSkeleton($attributeSetId);
        $attributeSet->save();

        $setup->endSetup();
    }
}

If you do everything correctly, you'll be able to see your custom attribute set among others when creating a new product:

Once you create product attribute sets and product attributes assign attributes to attribute sets programmatically.