Just with a few steps you can easily show your "selected" products on your storefront. If you wish to show one of your categories on your storefront just follow the steps below.
To show Specific Products from different categories to mention they are "On Sale Products", "Best Sellers", "New Products", etc. first you need to create a new category for these products and put them together in this new category.
(You can assign more than one categories to a product, no need to delete remaining one.)
1- Go to Themes >> Theme Manager >> Theme Settings menu of your Admin Panel.
2- On the new page, scroll down to the Featured Products field.
3- Select the category that you want to show on your storefront as "Featured Products".
4- Then click on SAVE. You can now see your products on your Homepage.
Also, You may not like the definition of "Featured Products". May be you want to show them as "Best Sellers" or "Favorites" etc.
All you need to do is scrolling down to the STOREFRONT LANGUAGE field in Theme Settings. Find "Featured Products and change the definition.
Well done! Enjoy your new feature of your Homepage and let people to find your best products easily.