Be careful, you may not want to become "more aggressive" when the market is at record highs. Two Vanguard funds I have added in the last couple of months are VNQ and VGRLX. Both of these funds are going to be held for years.
A simple way to become "more aggressive" is to simply change the year on your current retirement fund, for instance if your current fund is 2020 you can change to 2030 and there is your easy way to increase equities exposure, but again this may not be smart when we are at record highs.
I have been a vanguard client for years and your best advice is to call them and check out their online resources.
Good Luck