When visiting Mombasa be aware this is a poor country! If you show off your gold, diamonds, money and phone you may become a target for local thieves.

Ladies should not  walk around with handbags, ruck sack's etc.  Carry small amounts of money around with you, maybe in your bra, a money belt, or deep in your pockets if they are tight.  Maybe also carry two separate stashes; if you are unlucky enough to be robbed, give them the small amount and hope that they run off.

Don't wander off into the local villages on your own.  If you do go with a local guide, be aware that they may take you to their own home to meet their own families. Then you may be put in a bad posisition, as you may be expected to help out the family with some money buying food and sweets for the kids, and when kids in the village hear that there are sweets being handed out they will come from everywhere.

Don't go out and about with beach boys, as you may end up in some place from which you don't know how to get back to you'r hotel . Not all beach boys would do that, but it's probably better that you don't take the risk.

Local Matatus are fine for day travelling.  Most conductors, if you ask them, will be kind enough to re-arrange their passengers if you want to sit at the front with the driver rather than getting squashed in the back. 

At night get a taxi. Local are fine, but just make sure that you agree on a price with the driver first, so that you dont get charged a stupid price when you arrive at your destination. Don't be alarmed if there is a local with the taxi driver in front -- they also need to consider their safety.

When with a guide, make sure that you take details of his ID (hey should have a card).  Don't let some people start walking you around and telling you things around the tourist attractions.  You think they are being friendly and then you have them demanding  money at the end. They will tell you they have been your guide, while you are not aware of this.

Don't put down payments on anything.  Agree on the price of what you want to purchase. If it needs to be made then you tell them you will pay when you've received your goods.

Beach boys will offer you much cheaper safari that the local tourist companies.   Take care, though, as you may not be getting what you paid for, and don't part with any money!  Your guide will know the places to take you if you want to do a tour in the town of Mombasa and know that you will get what you paid for.  Most of them will accept card payment.

While this may seem to paint a bad picture on safety, please keep in mind that there are a lot of lovely things and places in Mombasa,  and there are also a lot of nice people.  Most of the time your hotel staff will be able to point you in the right direction without paying a fortune -- just tip them something small for their troubles, as these people work hard for very little money.  They will help you and make sure that you are not taken advantage of if you look after them a little.  You may also be suprised to find that some of the European people that may be wandering about a hotel may even be local, and they may help you with advice.