There are a few ways that you can go about this. Here is what you can look out for: 1. Adjust the size of your sweaters by changing the hook size, yarn weight, or number of stitches and rows. 2. Always refer back to the pattern's sizing instructions and charts for accuracy. 3. Since you will be crocheting the sweaters, measure your body proportions with a measuring tape. Measure your bust/chest, waist, shoulders, and arm length. Remember to leave extra allowances for your preferred ease and to avoid movement and mobility restrictions. 4. You can also compare the measurements with your existing sweaters for a precise fit. 5. Crochet a gauge swatch to ensure your stitch tension matches the chosen pattern. If you need more guidance, learn more about Crochet Gauges here.