Depending on your budget there is alot you can do.
What kind of stock are you planning on using? The OEM one will suffice, but there are better ones out there.
For scopes I recommend the leupold tacaticals, but the cheapest one that will suffice would be the bushnell elite 10x mildot, the SuperSnipers are a great scope for the money, but they are fixed at 10, 16, or 20x.
The harris bi-pod is a good choice.
I like the TPS steel rings and 20 MOA bases, but the seekins ones get good reviews too.
Heres what I did to mine...