The conditions we recommend for running a gel are:
We run a 1% agarose gel. Depending on the size of the gel/number of wells, we load 250 ng to 1 ug of mRNA. We dilute mRNA to 0.2 ug/uL, then add equal volume of NorthernMax Gly sample loading dye.

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For making a 1% agarose gel, we would use 50 mL of gel and 0.5 grams of agarose. Microwave the agarose until melted and allow to cool for ~10 min. Add 0.5 uL of ethidium bromide. Swirl gently to mix. Pour gel.