It is generally not recommended to add to your existing mattress to make it larger, as it could compromise the integrity of the mattress and affect its overall support and comfort. (It's a terrible idea and will probably cost more than buying a new mattress in a larger size)
Instead, if you need a larger sleeping surface, it's best to invest in a new mattress that fits your needs. If you don't want to replace your current mattress, you could consider purchasing a mattress topper, which is a layer of cushioning material that sits on top of your mattress and can provide some additional comfort and support. However, a topper won't actually increase the size of your mattress, and may not be a long-term solution for those looking for a larger sleeping surface. ( the AI is talking around in circles here? A topper of does not make your mattress larger)