I built a platform frame for my mattress, but would need to know more details before giving any instructions. What type of mattress do you plan on using? What type of look do you want? What are your reasons for wanting a platform? Do you want storage underneath? Are there any weight considerations? Do you just want a foundation or also a canopy? Do you plan to build a built-in headboard/bookshelf? Does the head of your bed need to be elevated for medical reasons? Do you want to make this basic functional or fancier? Do you want it padded or just solid wood? What type of tools do you have to work with and how much experience do you have in woodworking? There are unlimited personal preferences to be considered here. Exactly what are you seeking?

I'm still not picturing what you want. How high do you want it to sit off the ground? Would you prefer the flex of slats, or do you want a solid surface? If you like the design of your queen platforms, post a picture here. Do you want solid sides, down to the floor, or a space underneath (if so, how much space)? Do you want the mattress to set down into the frame or sit on top of it? If set inside, how deep do you want it to be? If you explore online, you'll see that there is no such thing as a standard platform bed. If you can describe what you want in more detail, I could give you the material list and describe how to cut it and put it together. I also need to know the exact measurements of your mattress (length, width & height).

You might want to check out some platform beds to find the design that you want. There are lots of different bed frames on the market. Some of them are very simple. Check around before you plan to get the overall look that you want. You can also make a platform bed with slats that will support your mattress.