#con-scripting

There are a few things that all Conlangers need, some of them you can figure out using just common sense, but some are not so straightforward.

Of course all Conlangers need a notebook, a pencil (NEVER USE A PEN!!!! You will be doing a lot or erasing.), and an imagination. Another thing that is nice, but you don't necessarily HAVE to have, is some knowledge of linguistics, and orthography. But as I said, you don't HAVE to have those, a lot of what you will end up doing when creating a language may just "come" to you. But when it doesn't, here's some sites that may help:

http://www.ancientscripts.com/

Very nice site with lots of different writing systems, some dead, some still in use (such as the Latin and Greek alphabets).

http://www.omniglot.com/

Like Ancient Scripts, but SOOO much better. It has dead and modern scripts, it has historical information about different languages, both dead and modern, it has conlang information, con-script information (and quite a few con-scripts), and probably more that I haven't found yet. Omniglot is a never ending chest full of awesomness.

http://fontstruct.com/

This will come in handy when your conlang is "done"(quotes because, technically, a conlang is NEVER done). Use it to create fonts for your conlang's script, so that fans of your conlang can use it on their computers (and possibly the internet).

http://conlang.org/

This is a must for Conlangers, if only because it is the official website of the Language Construction Society. Here you will find news, links, and more.

http://www.zompist.com/kit.html

Perfect for new Conlangers, the Language Construction Kit will take you through all the steps of creating your very first conlang (it won't do it for ya though, sorry. You still gotta do the work, this'll just help out a whole freakin' lot). 

I've been con-scripting since I was around ten (can't remember exactly, and neither can my mother), so I think I have a few tips that I can give to newbs (not to be confused with noobs). If I'd had these when I started it would have really helped me:

#1: NEVER make your con-script just another code. While making codes/cryptexes can help you get started on con-scripting (like it did for me), it will never satisfy you as much as a full blown script will, and it won't impress others as much either (if that's what you're going for).

#2: Don't use the letters of another script to make your con-script. It just looks stupid, and makes you look like a copycat. However, you can use another script to base your own off of, as long as you're going to make enough changes to the letters/runes/whatever-they-call-those-things-they-use-to-write-their-language-with to make it look original. My current project is based on the Latin alphabet, but only a few of the letters look like they originated as Latin letters. Most (but not all) of the letters have been reduced to a single pen/pencil stroke. You could do something like that, or you could take the opposite route, and increase the number of strokes used. Or you can combine them with the letters/runes/oh-you-get-it-by-now of another script to create something new. Or you could do something completely different. It's up to you. Just make it easy enough to tell the different between letters/runes/that-other-thing.

#3: Don't make the letters/runes/something rely on color. I know some people like using color to represent different phonemes, but it's stupid, and will make it near impossible for color blind people to read your script if you're not careful.

#4: Don't base your script off of Chinese, PLEASE!!! Chinese characters are beautiful, but they're hard to write, and take forever to learn.

#5: Ignore #4. Chinese characters are wonderful, and as long as you simplify them (or target people that have a whole lot of patience) there's no reason not to base the letters/runes/let's-just-call-'em-characters-from-now-on of your script off of them. #3 still stands though, color blind people (and dogs) need to be able to read too.

#6: If you're designing a script for English don't make an abugida (also known as a syllabic alphabet). English just doesn't work well with them.