Make sure your super confident going onto the rail and make sure you have enought speed to get onto the rail.
once your on it just keep looking at the end of the rail and tryjust do like you'd do on a park rail and try not to land in the stairs if you feel unstable, if one side is grass or something, it's beetter to jump off if you feel uncnifdent once youre on the rail then trying to get your balance after ward and catch an edge and fuck yourself up.
Remm,eber it's preseason, your prolly not as god as you used to be on rails at this time of the year so play it safe.
Way to many talented jibers hurt themselves too early on urban rails.
hope that helps.