You are definitely ready to start tanking SM operations. If you have yet to get Obroan relics from pvp definitely do that. They are a huge boost, that is kinda hard to see at times, and worth the time commitment.
Definitely try to run with people who you know when doing operations. These friends are more likely to help you learn the strategies which is very important for tanking. Secondly, I definitely recommend getting your off-hand first with your Ultimate Comms. Its usually a huge upgrade and if you get a set bonus piece (from arkanian or underworld) you wont have just wasted a 180 armoring.
EDIT: On the discussion about augments, find a set of gear you like, the way it looks, and will never change out. At that point start loading in augments and you will gain a lot of stats that are needed. Mitigation is more important than health for a shadow tank, therefore augments are a great boost. You can buy augments for not too expensive either. On my server, JC, the normal MK-9 augmentation kit goes for 50k with the actually augment going for like 30k I think, it has been a long time since I bought one. To augment your gear completely the first time will take over 1 million, so start knocking out those dailies on Oricon, CZ, Section X, etc... Also, Aelanis has been giving sound advice in all his or her posts I have seen. I agree with everything previously stated by Aelanis.