Whether you're fixing a leaking pipe under your sink, laying tile or scrubbing baseboards, these DIY projects will require that you kneel down. To keep your knees bruise- and ache-free, use kneepads or a portable mat. There are loads of styles and materials to choose from. If you need to get up and down and reposition yourself often, kneepads work great. On the other hand, if you can work from the same spot on the ground, a portable foam work mat or even an automotive vinyl work mat might be more comfortable. Kneepads cost around $5, while mats are more costly.