How to Make a Pillow Bed
To make a pillow bed, flatten 2 pillowcases and lay them on top of one another so all of the edges are aligned. Once they are aligned, poke 3 to 4 sewing needles through them around 3 of the sides. With the 3 edges pinned, set the pillowcases on a sewing machine so the needle is ⅜ of an inch from the edge of the unpinned side. Slowly feed the pillowcases through the sewing needle, making a straight seam across. Then, unpin the edges and sew another pillowcase along the longer edge. Keep sewing on additional pillowcases to each side until you have a row of 5 or 6. With all your pillowcases stitched to each other, put the pillows back in and fold the opening of the pillowcases underneath so they don't fall out.
Check that your pillows fit snugly in the pillowcases. Take one of your pillows and insert it inside the case to see how tight it is. Make sure the pillow fits tightly against the seams of your pillowcases. If not, get larger pillowcases or smaller pillows. Use identical pillowcases and pillows so you don't have to take multiple measurements and so your pillow bed matches. Stack 2 pillowcases on top of one another and pin them around 3 edges. Flatten your pillowcases so they're wrinkle-free. Lay one of the pillowcases on top of the other so all of the edges are aligned. Once the pillowcases are lined up, poke 3-4 sewing pins through them around 3 of the sides. Leave one of the long sides unpinned so you can sew it easily. Sew 3⁄8 in (0.95 cm) in from the unpinned edge of the pillowcases. Set the pillowcases on a sewing machine so the needle is ⁄ 8  in (0.95 cm) from the edge. Make a straight seam across the long side of the pillowcase by slowly feeding them through the sewing needle. Once you finish your seam, remove all of the pins from your pillowcases. You can also sew the pillowcases by hand , but it will take more time to complete. Add 4-5 more pillowcases to each side. Unfold the pillowcases you've already sewn together, and line the edges of another pillowcase on top just like before. Sew along the long edge of the pillowcase to combine them. Continue adding pillowcases until you have 4-5 attached to one another. Make sure you're always sewing along a new edge as opposed to one that you've already sewn together. If you're making a pillow bed for a toddler or child, you only need to use 3 pillows. Add as many pillows and cases as you like. Put your pillows into the cases to finish your pillow bed. Insert the pillows into each of the pillowcases so they fit snugly next to one another. Fold the opening of your pillowcases underneath the pillows so they don't fall out of the case. Lay your new pillow bed on the floor to use as a cushion when you lie or sit down. You may also sew the pillowcases closed if you want a permanent pillow bed. Fold the long sides over 15 in (38 cm) and 22 in (56 cm) so they overlap. Lay an extra-large twin-sized sheet right side up on the floor. Fold over one of the long sides by 15 in (38 cm) and pin the edges in place. Fold the other long side of the sheet over 22 in (56 cm) so it overlaps the first side. When you're finished, your sheet should measure 28 in (71 cm) wide. If you don't use a sheet, you can use any piece of fabric that's 66 in × 96 in (170 cm × 240 cm). Sew along the short edges to finish the ends of your pillow bed. Feed the short end of the sheet through the needle of your sewing machine. Keep the seam about ⁄ 8  in (0.95 cm) from the edge. Once one side is sewn together, sew the other short side of your sheet. If you don't have a sewing machine, you can also sew the sheet together by hand. Turn the sheet right side out. Open the middle of your sheet where the folds overlap one another. Flip the sheet so the side you want displayed faces out and your seams are inside. Lay the sheet flat again so there are no wrinkles. Make seams 17 in (43 cm) apart along the length of the sheet. Mark out every 17 in (43 cm) down your sheet using a fabric marker. Make straight seams using your sewing machine where you've marked the fabric. Make sure your seams go from each end of the sheet. If you're using differently sized pillows, measure their width and adjust the measurements on your sheet accordingly. Put pillows inside each compartment. Lift the flap on your sheet and insert a pillow between each of your seams. Set the pillow bed on the floor once it's finished so you can lie or sit on it. Be careful if you're using firm or extra-firm pillows since they may be more difficult to get into the case and rip your seams. 
Check that your pillows fit snugly in the pillowcases. Stack 2 pillowcases on top of one another and pin them around 3 edges. Sew 3⁄8 in (0.95 cm) in from the unpinned edge of the pillowcases. Add 4-5 more pillowcases to each side. Put your pillows into the cases to finish your pillow bed. Fold the long sides over 15 in (38 cm) and 22 in (56 cm) so they overlap. Sew along the short edges to finish the ends of your pillow bed. Turn the sheet right side out. Make seams 17 in (43 cm) apart along the length of the sheet. Put pillows inside each compartment. 