Hi Tolu,

I hope this will help!

First create the options you need, and put them in a dictionairy

private readonly IDictionary<string, IProductOption> _sharedOptions = new Dictionary<string, IProductOption>();

   private void CreateSharedOptions()
    {
        var productOptionService = MerchelloContext.Current.Services.ProductOptionService;

        var size = new ProductOption("Size") { Shared = true, UiOption = "select" };
        size.Choices.Add(new ProductAttribute("Small", "sm") { SortOrder = 1, IsDefaultChoice = false });
        size.Choices.Add(new ProductAttribute("Medium", "md") { SortOrder = 2, IsDefaultChoice = false });
        size.Choices.Add(new ProductAttribute("Large", "lg") { SortOrder = 3, IsDefaultChoice = true });
        size.Choices.Add(new ProductAttribute("X-Large", "xl") { SortOrder = 4, IsDefaultChoice = false });

        var colour = new ProductOption("Colour") { Shared = true, UiOption = "select" };
        colour.Choices.Add(new ProductAttribute("White", "white") { SortOrder = 1, IsDefaultChoice = false });
        colour.Choices.Add(new ProductAttribute("Black", "black") { SortOrder = 2, IsDefaultChoice = false });
        colour.Choices.Add(new ProductAttribute("Grey", "grey") { SortOrder = 3, IsDefaultChoice = true });
        colour.Choices.Add(new ProductAttribute("Blue", "blue") { SortOrder = 4, IsDefaultChoice = false });

        productOptionService.Save(size);
        productOptionService.Save(colour);

        _sharedOptions.Add("size", size);
        _sharedOptions.Add("colour", colour);
    }

During a product creating process, you need to add the options to the product.

private void AddOptionsToProduct(IProduct product)
{
    foreach (var option in _sharedOptions)
    {
        product.ProductOptions.Add(option.Value);
    }
}

var product= merchelloServices.ProductService.CreateProduct("product", "product-01", 13.99M);
    ... add all the product variables
merchelloServices.ProductService.Save(product, false);

AddOptionsToProduct(product);
merchelloServices.ProductService.Save(product, false);

Hope this helps!

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