Well, I have not started this topic as yet, but from the question, you have to discuss these points:
1. Signfiance of Egypt's military campaigns - brief introduction, did it intersect with the political conditions, laws etc..
2. How it relates to new kingdom - correaltion between the two - did it provide strength, the ability to dominate other nations, national security and defence?
3. ASSESS - You have judge the significance throughout your essay - Is it significant or not significant (important) and to what extent?
4. Provide EVIDENCE!! (You MUST do this) - might be quotes from written sources or artefacts unearthed, frescoes, wall paintings etc...
5. Structure it well - have a clear focus and be succinct - brief outline of the military is fine, but do not ramble on
Hope that helps! Once again, I have not started this topic yet, but from the nature of the question, I was able to predict the above mentioned points!