I was in the same position with 401K left behind. Find a co. you're comfortable with and they literally handle everything. Look into schwab, fidelity, etc. and their sites almost always have a rollovers button. It was as simple as clicking the rollover, following directions for free account opening and then providing them with acct #'s for the old account and voila - it rolled over. It really comes down to comfort and preference with the site/interface. You can choose your own funds, choose target date funds and new to schwab are target date index funds - low cost/fees.