Altered Clothing: Hip Fixes And Transformations... -

Sew in a long strip of contrasting fabric (like lace, leather, or a different denim) from the waistband down to the hem. This adds width and a designer look. The "V" Gusset For minor tightness at the very top of the hip:

When adding panels, ensure the fabric grain of the new piece runs in the same direction as the original garment to prevent weird twisting. Altered Clothing: Hip Fixes and Transformations...

Cut a small vertical slit at the side seam or back waistband. Sew in a long strip of contrasting fabric

Turn the garment inside out. Pin along the side seams, starting from the waist or mid-thigh and tapering into the existing seam. Altered Clothing: Hip Fixes and Transformations...

This is only possible if the garment has a generous (extra fabric inside the seam).