Beginning to mission make is nothing more than clicking elements and typing codes that perform specific tasks. Alls you need to do is learn them! In fact, the hardest part of a mission isn't the actual execution of design, it's the ideas! Usually the Mission Ideas location in the forum can heal that wound but nothing is more effective than your own genuine and unique
ideas. Let's face it, raiding towns, tank assaults and stealth missions are common. You'd struggle to place anything unique into the community and because of this most reviewers dismiss most apects of originality (an exect copy of a mission wont do you any favours
Once you've decided on an idea it's time to get to work. Start of by dedicating alot, if not most of your time reading guides from the basics such as lighting a fire to more advanced camera scripting. Take a look in the forums for help & advice on various subjects. You don't need to post whenever you have a problem
(scripts don't make a good missions by themselves, you know)
Unfortunatly I only agree partially, they don't make good missions themselves but when used they turn 5-rated missions into 8's and 9's. Remember, SCRIPTING ENGULFS 25% OF YOUR OVERALL MARKS
! So ensure you use them as often as possible.
Download Amalfi's PBO decriptor. With it, you can take someones mission and view it in the editor. From there, you can learn how they made it and with which codes, scripts and editor-driven features.
Most of all: take advice, continue to learn and have a crate of Pepsi, an excuse for your girlfriend and plenty of music for those long nights in editing. Take your time with all missions!
Since your after mission idea's, heres a few: convoy attack, Shilka stealth mission, camp raid, patrol mission. I'm sure you can think of more!
Also one more piece of advice - USE THE BETA FORUM
! You'll get more help from there than in any other forum!