You are ready to start
Start bowing on the loose strings without fingers on. Listen and get a good tone. Check in the mirror if the bow is moving perpendicularly across the strings. The contact to the strings should be in the middle between the fret board and the bridge.
Move the bow slowly across the strings. Make short and long notes. Use the whole bow or just the tip of the bow. If you get a screechy sound, look into the mirror and check the position. Correlate what you see with what it sounds like.
If the position is in the middle between the bridge and the fret board and the bridge, and the bow is moving perpendicularly, and the sound is still screechy, try to adjust the force that you apply on the bow onto the strings. You should not apply force here.
Is it too hard or too soft?
The feedback from the mirror will help you to fast get a good sound out of your violin.
Continue to make this exercise a couple of minutes every day for the first half year you are playing. If you get your bowing technique right from the start you will learn to play violin much faster.
You should make the exercise of bowing on loose strings in front of the mirror to your start exercise every day.
Run the exercises for at least week before you go on to the first melody. Make sure that you get a good feel while you are bowing, and check that you are relaxed and the bow is right between the two strings. Check that your style is looking like on the following pages.