I would suggest the following:
- If you have access to your boss's email Inbox, go through it as that will be a good place to start. As you go through the items, you will have questions about meetings he or she is attending, questions about events they may or not be attending, etc. Also check their Sent items in case the answer lies in there. Sometimes I have checked the Sent items to see my boss has already emailed the organizer to send her regrets to a meeting.
- Review the items you want to discuss before the meeting with your boss. Sometimes you may have a list of items, but don't get to see your boss face-to-face for a few days. It is better if you go in prepared. It will be a better use of both your time. You do not have to spend a lot of time reviewing, but quickly go through the list so you are familiar with each item.
- Bring a notepad and pen, or if you prefer electronic, then bring your laptop.
- Some people like to use their cell phones and write on the Notes app any actions they have, but unless you are provided with a cell phone from your organization, I would not recommend using your personal cell phone for work related items. As convenient as it may seem, it is always best to separate your work and personal life. If your position requires a cell phone, then your organization should provide one. There are also work privacy issues that could be compromised if you combine the two.
- I bring a folder with printed emails/letters etc. that I have questions about or want to provide her with information. This can also be done on your laptop by making a list of what you need, but whichever method you use, it should be available at a moment's notice. Sometimes my boss has called me from out of town and asked if I had anything to discuss while she has me on the phone. I grab my folder and go through the items with her that I need an answer to sooner rather than later. The rest I leave for our regular meetings.
- Meet at the beginning of the work day. If you meet too late in the day, you will undoubtedly leave the meeting with a whole slew of action items that may not be able to wait until the next day. If you want to leave work on time, have your regular meetings with your boss in the morning.
My current boss is not good at answering emails and quite frankly, I don't really want to clutter up her Inbox with my items when I can ask her by phone or in person. Previously, in another position, my boss worked great by email and always knew to check anything from me right away. If that is the case for you, then you should make sure every email you send counts and you do not send reply to all emails or any other clutter that they don't really need to see.