Upverter’s Generics feature is a great way to add passive components to your schematic whose manufacturer part numbers can be chosen later. This is especially useful for adding decoupling capacitors and pull-up/down resistors – you simply specify the value and other parameters you want and don’t worry about finding an orderable part until later.
This is much better than other workflows where you have to create a new resistor/cap in the library for each value you want.
Here’s a video showing how to make use of this feature.