You don't. A millilitre is a measure of volume, with dimensions [L3]. A milligram is a measure of mass, with dimensions [M]. The two measure different things and elementary dimensional analysis teaches that you cannot convert between measures with different dimensions such as these without additional information.
As a simple mental exercise consider a millilitre of air and of water. They will have very different masses.
You can not convert mg (weight) to volume (ml).
262 mg to ml
convert 6 mg to ml
Only if the density or concentration is 1 mg/ml
Does not convert; milligrams (mg) and grams (g) are measures of weight or mass and mL (milliliters) is a measure of volume.
Milliliters does not convert to milligrams.
Does not convert; milligrams (mg) and grams (g) are measures of weight or mass and mL (milliliters) is a measure of volume.
Does not convert; milligrams (mg) and grams (g) are measures of weight or mass and mL (milliliters) is a measure of volume.
Does not convert; milligrams (mg) and grams (g) are measures of weight or mass and mL (milliliters) is a measure of volume.
Does not convert; milligrams (mg) and grams (g) are measures of weight or mass and mL (milliliters) is a measure of volume.
Does not convert; milligrams (mg) and grams (g) are measures of weight or mass and mL (milliliters) is a measure of volume.
Does not convert; milligrams (mg) and grams (g) are measures of weight or mass and mL (milliliters) is a measure of volume.