There are several activities that would be good for this Samhain evening, but I am going to list the ones that I enjoy the most.
Reading the Tarot Cards
This is the night that I like to do an overall reading for the coming year. I look for the possible trends and obstacles that I will have to confront in the months that follow. Since I have been reading the tarot regularly for the last 40 years I can pretty much remain objective to the information coming to me. If you have some friends who can also read the cards it would be fun for everyone to give each other a reading on this night. Remember to take notes as this is an overall indication of what the coming New Year has in store for you.
Crystal Ball Gazing
This is another way of communicating with yourself and the spirits that are around you. (A note of caution when attempting to communicate with spirits: Always do so in a circle of protection and keep a white candle burning and sage or some other form of protection incense smoking.) If you wish to speak with the spirit of a departed loved one, place a picture of them on your altar by the crystal ball. Bring an image to your mind of the happiest time you had with this person. If you do not have a picture, write the person's name three times on a piece of parchment and ask him/her to join you. I find it doesn't go well to "summon" a spirit, that always seems like a command. I prefer to invite them to join me. Remember that a person who has crossed over less than a year and a day may not be available to communicate.
This is not an activity for the novice witch. However, it can be a good one if it is lead by an experienced medium. (I personally do not attend them because I have a Moon square Neptune aspect in my natal chart and my astrology teacher warned me that this was not a good aspect for participating in them. It would be too easy for a spirit to gain control over me in that situation. )
That being said here is a link for a Séance that you can do:
Scrying Mirror: AKA Witch's Mirror
The scrying mirror is a black mirror and you use it with the light of a single candle. Here is a link to give you full info on this subject:
This night is good for all other forms of divination, but remember to play it safe and keep your activities within a circle of protection as this night is the night that the spirits walk among us.