Allow me to echo the general opinion of the TB community:
There is no "proper" order - only a few general guidelines based on what most people seem to prefer.
But since you're new to this, I'd be happy to lend you a hand. You're on your own afterwards for your signal chain.
The Boss TU-2 doesn't even have to be first - I've seen it at the end of chains, or in other places too. The advantage to having it at the end? Total muting, even if other effects are on. The disadvantage? If other effects ahead of it are on, you won't be able to tune accurately. Otherwise, as long as it's the only pedal on when you're tuning, it doesn't matter where it is in the chain.
The others depend on how you use them. Most people prefer modulation effects (like chorus) after distortion. Envelope filters... well, that's up to you. Some prefer the craziness you get by running distortion => filter, while others like the more subtle filter => distortion.
Wahs follow a similar principle. Guitarists in particular tend to love wahs before their distortion. But some famous bassists like Cliff Burton produced those screaming solos by running distortion into their wah.
And the SansAmp... well, it depends on how you use it. If you're using it as a DI, keep it at the very end. Otherwise, you could put it wherever it sounds best.
It really all narrows down to what sounds best to you. But here's a chain you could start with, based on my own preferences:
AMP <= SansAmp <= CEB-3 <= BassBalls <= (Wah) <= RAT <= Cream Pie <= BASS