My tips are not about the best way to play the game nor the mechanics..
My tip is based on Leadership, what it means to be a Commander-in-Chief.
One of the biggest parts in my opinion, is being an adhesive to the alliance. It is not just worth brining 49 players into an alliance without being their bond. It is down to you as the CiC to make everyone feel welcome, unite them as you would your own family and treat them so. It doesn't matter how experienced you or your alliance is you have nothing to prove to each other, Ego can be an alliances biggest killer not just the rival alliances.
Knowledge of all aspects of the game would be a massive advantage, this will prove to you Brothers and Sisters that you are capable to keep control, but never demanding anyone to do something by the click of your fingers. Treat your alliance members as if they were the CiCs of your alliance because all in all you are all Commanders right?
Get to know the people that serve with you because you will stand beside them for month and months to come. Some will become so loyal to the cause they will follow you once more into another server and another and so on.
There are several things you must be able to enlighten your alliance with, this goes to new or old players, key points that must be remind the alliance from time to time to keep the peace...
Communication, Coordination, Friendship/Loyalty, Dedication, Morale. These are fundamentals of keeping an alliance together, just one of these lost can prove fatal to the alliance. Communication is strongest of these 6 which is used for clear Coordination to better you strategies and tactics via PvE or PvP. To build friendships with those you stand beside, these friendships doesn't just need to be in your alliance alone but all alliances that are allied with you. Alliances coming together as one to forge an unstoppable family of alliance, a force to be reckoned with. Dedication to you alliance is also a asset to the alliance as a CiC. Being one of the most active in your alliance proves to your members you are most capable of running it, keeping an eye on forums and messages updating them or sending them out often. Your words will be heard most and people that are just as dedicated as your will follow them. Lack of dedication will degrade your alliance, players will lose faith in your abilities to control and direct your players. There will be no structure nor morale and the alliance will collapse from within.
Which brings me to Morale, my favourite point. As a Viking Re-enactor and more to the point a standard bearer/chaplain keeping the morale up with powerful speeches or actions can be one of the most uplifting things to do in an alliance. Not only can you have fun doing it, you make those around you feel happy, they feel apart of something strong and fierce. The alliance for example can be flowing slow both in PvE or PvP but simple paragraphs that can get the blood rushing can prove effective indeed, i know this from much experience. Wars can be won using this tactic by showing your alliances what it means to be apart of the family they stand in, what it would mean for all of them to victorious after a long, daunting and stressful day, week, month or even year.
All in all no matter what anyone says leading an alliance is the hardest thing to do in this game, dedicated CiCs would waste no time keeping an alliance together so much so they lose track of their own game time to keep everything in check.
There is so much more to it than just this and through each world I've been in, I've witnessed many different leadership styles, some better or worse than others. Whatever the case i commend anyone that steps up to the CiC role, it is a long and stressful road but yet very satisfying when everything falls into place like a good ol game of Tetris!