How do I pick the right funds inside my 401(k)?

Keep it simple and cheap. Most 401(k)s offer a limited menu, so start by finding the low-cost index funds — a total U.S. stock market or S&P 500 fund, a total international fund, and a bond fund — and check each expense ratio. Anything under about 0.20% is good; over 1% is a red flag. If choosing and rebalancing feels overwhelming, a target-date fund matched to your expected retirement year does it all in one holding: it diversifies globally and gradually shifts to bonds as you age. Match your stock-versus-bond split to your time horizon and risk tolerance — younger investors can hold mostly stocks. Avoid chasing last year's top performer; past returns don't predict future ones. Don't leave money sitting in the cash or money-market default option. Find a starting allocation at wealthserene.com/tools/portfolio-builder.