There are multiple options available.
1. Updating to 4.x via game card, then installing MSET exploit, creating emunand (via GW Launcher is easiest), then installing rxTools MSET and get rxTools (I recommend 9/28 nightly but 10/02 is supposed to be good too.)
2. Updating to 6.x via game card, similar to the previous one, except you can't use GW Launcher (don't think it works on browser under -7), but Decrypt9 can backup sysnand and I believe create an emunand partiton + write copy of sysnand to it so you don't need GW launcher for it.
3. Updating to 9.2 via game card, using Cubic Ninja with Ninjhax2 to load rxTools (can use Ninjhax2 to load Decrypt9 as well so you can backup sysnand and create emunand.)
As I don't think GW Launcher go.gateway-3ds.com exploit works on browser lower than -7 (someone might have to try)