Thank you john for your answer,

I appreciate it to have more comment

You can use SybrGold from Invitrogen. It will stain both DNA and RNA (like silver). 5 microliters and 5-15 mnin staining in diluted TBE (pH=8,0 is important) in dark is good enough to see about 10ng of DNA in a band. Use vinyl gloves.

Good luck,

Przemek

The cheapest and easiest way is by using ethidium bromide. Let the gel stain for a few minutes in a standard EtdBr staining solution (just as for agarose gels) on an orbital shaker. Wash with tap water briefly. Be careful not to tear the gel. If you don't see bands, continue staining for another 5-10 min.