The first main thing you need to take down Titans as a Pilot is the Grapple. If you want a chance to even get CLOSE to a Titan, you're going to need it. You can use it to get on a Titan easily without the risk of being accidentally stepped on, and after you jump off the first time, you can immediately get back on, because it gives you 2 uses before cool down. The second thing you'll need is an area with a lot of buildings for you to escape to if you're hurt, or your Grapple needs to recharge. If you try to take down a Titan such a Scorch at Legion in an open area, they will probably kill you before you get to them. If you don't like the Grapple, you can try Cloak or Phase Shift, both of which make it easy to get onto a Titan. if a Titan deploys his electric smoke, you should get off a soon as possible (you can terminate the rodeo procedure by tapping the jump button) and then get back on once the smoke has cleared, because the smoke has a long cool down. In the case that the Titan has the double electric smoke kit, you should just do the same thing. I would recommend the Battery Pack Boost, because if it's active, it automatically puts a grenade in your hand when you're rodeoing a Titan, and the grenade does more damage than taking out a battery. I would also say that trying to board the Titan from the from is MUCH riskier than boarding from the back, as the Titan can melee you out of the air. Especially with the Ronin, who has a much bigger melee range than your average Titan. You should also try to drop straight on top of the Titan, which requires less time than climbing up the back or climbing from the from all the way to the back. You can also use the ability that makes you harder to detect while rodeoing. If you're using an Anti-Titan weapon such as the Archer, you should try to get behind the Titan and make sure it's not about to turn a corner, because then the rocket will miss.
These are all my tips for taking down Titans as a Pilot, and I hope they're useful to you.
I'm currently a G3 Pilot and I've been using these techniques to take down Titans the entire time.