I remember making Danish Paper Hearts with my mom when I was a kid, and thought it would be simple to crochet one. It's done all in single crochet stitches.
This one is fairly big, I used a size H hook and worsted weight cotton (Peaches & Creme). But if you want to create your own pattern for one with more than 3 strips, it's a little math. You want the strips to be twice the width of the top of the strips joined. An easy way to figure is to measure the width of one strip, multiply by the number of strips you want, then again by 2. So with mine, the strips are 6:1 length:width, plus one extra row for a bit more room to weave.If you want 4 strips, it will be 8:1.Crochet one strip, and measure and count your rows, then make all the strips for that color, and repeat for the other color. You can use any stitch you like as long as the strips are the right length. So if your base row is 5 stitches wide and 1 inch, and you want it to have 3 woven strips, you'll need to make each strip 6 inches plus one row for ease.
Join the strips across the top and bottom with a row of single crochets in each single crochet. So my strips were 4 stitches across, and my top row of single crochets was 12 single crochets(4x3). The top and bottom of each side is a half circle, I did mine in single crochets, but if you wanted to, you could do it in another stitch, but the finished width across the bottom should be equal or close enough to ease to the width of the joined strips.
Make 2, contrasting colors looks best I think. Fold them each in half so the half circles at the top and bottom meet.
When you weave them together, you won't be using an over/under weave, but instead, it's around and through. One side will sandwich the other side, then you pass the folded strip through the next strip, then sandwich the strip from the other side again. So the first and second set of strips alternate like this pretty bad illustration. If this doesn't make it clear enough, check out the paper instructions I linked to at the start of this.
Alternate that way,since my pattern is only 3 strips, the final row is just a repeat of how you wove the first one.
You can either stitch the top closed to use it for a scrubbie or tawashi, or you can make another strip and sew it on with decorative buttons to make a basket. I haven't decided what I'm doing with mine yet. The woven parts are 4 layers of crochet, and the half circles on the top are 2 layers of crochet, so it would also make a serviceable trivet made in a non-synthetic yarn that's reasonably heat resistant.
The pattern for mine:
Using a size H hook and Peaches & Creme cotton.
Strips: Make 3 each in 2 different colors
Chain 5, chain doesn't count as first single crochet here or throughout.
Row 1: Single crochet in second crochet from hook, crochet across. 4 stitches
Row 2-31: ch 1 to turn, single crochet across.
Pull yarn through last loop on hook, and break off.
Single crochet across the top and bottom of each set of strips. (12 stitches). Pull yarn through last loop on hook, and break off.
Make 2 each in both colors.
Magic ring or chain 2.
Round 1: 3 single crochet in first chain or magic ring. (3 sts)
Round 2: ch 1 to turn, 2 sc in each stitch (6 sts)
Round 3: ch 1 to turn, 2 sc in first st, 1 sc in next st, 2 sc in next st, 1 sc in next st, 2 sc in next st, 1 sc in last st (9 sts)
Round 4: ch 1 to turn, 2 sc in first st, sc in next 2 sts, 2 sc in next st, sc in next 2 sts,
2 sc in next st, sc in next 2 sts (12 sts)
Round 5: ch 1 to turn, 2 sc in first st, sc in next 3 sts, 2 sc in next st, sc in next 3 sts,
2 sc in next st, sc in next 3 sts (15 sts)
Round 6: ch 1 to turn, 2 sc in first st, sc in next 4 sts, 2 sc in next st, sc in next 4 sts,
2 sc in next st, sc in next 4 sts (18 sts)
Pull yarn through last loop on hook, and break off leaving a tail to stitch the half circle to the strips.
Stitch the half circles to the top and bottom of each set of strips. Weave as explained above.
Make a hanger or stitch half circles together to make a scrubbie.
I'll make a real post in a minute or two.