This is a very underemphasized step – if you have an inappropriate bedframe, your comfort and the life of your memory foam mattress can be significantly reduced.
What do I use?
Your bed frame needs to be a flat surface that doesn’t bend or move. This can be anything from the floor, to some box springs or platform beds.
The floor isn’t the best choice. Simple hygiene dictates that it’s going to be rather difficult to clean the carpet near the bed, plus little things like spilling a glass of water become a far larger issue than they need to be.
A box spring may work, as long as it provides a flat surface that doesn’t yield. Five points of support are the suggested minimum (posts at all four corners, and one at the center). If you can push on the middle of the boxspring and it transfers this load nicely to its supports without deflecting appreciably, it’s probably a good fit. Don’t use boxsprings with padding, that have a “spring” to them, or that clearly deflect when you apply load to them.
What I did
I used a simple platform bed like the MALM bed shown on the right from IKEA. To ensure five points of support, I put a few textbooks (hey, I was on a budget) under the center beam.
There is also a choice between rigid and flexible supportive bed slats, pick the rigid ones.