There are three different ways to do this.
1. If the sub has LCR inputs for splitting out the low freqs then you can use it and leave your surrounds un-bass managed. This can be done with certain JBL systems, but other subs only accommodate left and inputs, so you can't use them for surround system BM.
2. Get a dedicated bass management controller. Blue Sky makes a very good one called the BMC that also has an ethernet remote with master volume, channel trims, solos and mutes for surround systems.
3. If you have a processing box like the BSS BLU16 (there are others), it will have crossovers, summing mixers and routing options so that you can design your own bass management system and it can also handle delays for time alignment as well as monitor EQ and calibration interfaces.
I have used all three methods, but currently am using the bass management in my JBL 6312 sub for the front speakers with no BM on the surrounds. It's easy and sounds excellent with my particular system, but if your satellites are small, you may need to use BM on your surrounds as well, in which case you need to use one of the other methods (unless your sub has 5 inputs, which I haven't seen). The Blue Sky BMC retails for about $1400 I think, and is very simple to set up and use. The BSS BLU16 costs closer to $3000 and is more complicated to set up, but it also offers all the other functions that are very important to a properly calibrated and EQed system. I bought a used BSS Soundweb 9088 on eBay for under $500, which is essentially an older version of the BLU16, and it works great. I use it for Monitor EQ, time alignment and calibration and use the sub for BM. I used to use the 9088 for BM for my previous surround speakers, because the sub only had 2 inputs for the front speakers, but decided to try out the JBL 6312's BM when I bought new speakers. It works well.