Firstly, it is recommended not only to let the old oil drain, but also to move the engine crankshaft 5-7 times to remove the remaining oil from the lines. It is even useful to flush the engine; for this purpose, a special flushing oil is made, which lasts 20-25 minutes, allowing the engine to work in different modes.
When changing oil, always change filters. Old ones, although washed, will be like a fly in the ointment in a barrel of honey.
Oil should be changed indoors, where there is no dust and wind.
When checking the oil level in the crankcase, the rag with which the meter is wiped must be clean. Even small particles of dust that get into the engine significantly reduce its service life.
When changing the oil, the gasket of the oil outlet bolt or the filter housing also changes (if there is one). It is included in the oil filter kit.
After changing the oil, it is useful to note the current mileage of the car, the date of the change, the type of oil, so that there are fewer problems with the next change or addition.
You should not be afraid that the oil will turn black after 1000 km of run. This indicates that it is correct "works" - accumulates carbon deposits in itself, washes the surface of parts.