You get bots in purple science. They're too slow at that tech level to be very good for high volume intermediate products, but they're excellent in a mall for making factory construction materials.
You also get hand crafting tools, so prior to having a bot mall, you can pump up your hand crafting speed and make some belts yourself. When you craft, most of your effort goes into the same intermediates over and over. Instead of focusing your efforts on automating a sngle product all the way from start to finish, focus on automating one intermediate, and then another. The more intermediates you automate, the faster your hand crafting will go as you can pick up stacks of increasingly expensive intermediates.
There aren't really 12 steps to automate conveyor belts. There is 1 single step to automate conveyor belts. Everything else is a material that you'll need for more than just conveyor belts. If you keep making the same materials over and over again repeatedly in different builds, your factory is going to have a lot of redundancy and be much more sprawling than necessary. Each item that goes into a belt is something that could be on your bus. Then it's only 1 step to make a fairly basic intermediate, and 1 step to combine it into something else.
Factory Planner and Helmod have their uses, but they don't have to dictate your building style. If an intermediate isn't on your bus, make it a single time for everything that will eventually need it rather than making it over and over again. If you build a bus style, at least for your key intermediates and early building materials, then you factory can never be more complex than the number of items you have, since you'll have at most 1 construction step making each possible material. When you eventually get a bot mall you can use your intermediate bus to feed the bot mall with raw materials. You don't want to go full bus and make lots of expensive buildings just to put them on belts.