I've had them, evil things! I have an ointment called Sheriproct on prescription which is fantastic stuff, numbs the pain and makes a huge difference.
Are your bowels normal? If so I'd be loathe to mess about with them. If you are a bit loose then you can get fibresure sachets in places like Boots which you can put in drinks and give you that extra bit of fibre. I used to have it in diluted orange cordial and couldn't tell the difference at all.
If you are sorer round the outside as well, I often use something cooling like Banana Boat Aloe Vera gel or aqueous cream (can store it in the fridge) for some additional relief, never "internally" though. I get this a lot though often mine are very very loose (like water) and feel almost acidic coming out (not sure if it's my malabsorbtion or just as it gets so sore it burns so much).
As bednobs said, lots of water, dry is definitely not good with anything like a fissure...ouch!!!
Are you going somewhere hot? May be an idea to consider your wardrobe to make sure you are comfortable around there and don't get hot or sweaty as I find this can make it worse and more uncomfortable, especially if you have any external soreness as well.
Might be an idea to search out some of those extra soft toilet tissue/wipes to take with you, just making sure you are dry enough afterwards, especially if in hot weather.
Any blood which doesn't look fresh or from something like pile or fissure, mucus, bowel changes or if the pain continues, definitely get it checked out.