For 401K, try to avoid individual stocks

The key for 401K success is steady growth with controlled risk. Individual stock may give you a quick gain if you concentrate and if you hit it right, but can let you lose shirts (or skirts haha) if you hit it wrong.

- Have broader EFTs (VTI, VOO, VB, VO, VWO/EEM...) as core holdings

- Use sector ETFs to tune according to market: Vanguard & Fidelity have lots of fee-free ETFs. (If you have employer sponsored brokerage, you may have to pay transaction fee).

Housing: XHB, ITB, VNQ,  ...

Materials: ...(there are a lot)

Energy: VDE, OIH,....

Check out the Vanguard & Fidelity sites.

Fidelity has a great ETF chart/mapping graphics tool.