You may not choose to wean you baby until 6 months old, in which case the purée recipes in my 'first tastes' section are fine to introduce at that stage. We decided to wean our little girl at about 4 and a half months old because she was hungry and breast milk alone wasn't quite enough for her. She had been sleeping through the night since she was 2 months old and going 4 hours between milk feeds throughout the day but at 4 and a half months old she started waking early in the morning and not lasting 4 hours between feeds in the day time. She took to purée very quickly and immediately went back to sleeping through the night and lasting between milk feeds again. Your baby will let you know when they are ready!
The advantage to weaning slightly before six months is that your baby won't actually eat much of anything initially and at this stage it doesn't matter. This allows you to approach weaning in a relaxed and fun way, which means that meal times don't need to become a battleground - if you are relaxed then your baby will most likely be relaxed. Before they are six months old, they are getting everything that they need from breast milk or formula and in weaning them early, you are giving them the opportunity to taste food and explore what it is like to eat; if they really don't take much in then you don't need to worry about it as they are still getting what they need from their milk. Then, by the time they get to six months old, they will probably have got the hang of eating so they will actually ingest at least some of the food! However, if you only starting the weaning process at this stage then it can get quite stressful for you, worrying that they aren't taking anything in. Weaning before six months also means that they are getting their 'first tastes' early, then at around six months you can start giving them meat and lentils, amongst other things, mixed in with the vegetables that they have become familiar with. This is quite important as meat is a very good source of iron, particularly red meat, and once babies get to six months old they need iron in their diets as they have completely used up the supply that they are born with.
I think that the first stage of weaning is really about giving your baby simple purées of just one fruit or vegetable initially, then combining flavours if you wish. It does seems a little boring giving them pain carrot or apple, but this is how they develop their understanding of flavours. They don't know what a carrot tastes like, so if you constantly give them mixed vegetables, they don't know what each one tastes like on its own. So my advice would be to make relatively small amounts of one-vegetable or one-fruit purée and freeze them in small pots or ice cube trays so that you can bring them out when you need them. Once they have tried some fruits and vegetables on their own, you can try mixing them up a bit, and if you have frozen a few cubes of various different fruits and vegetables then you can just defrost the ones that you want to combine, for example a cube of sweet potato and a cube of carrot, then mix them.
Personally, I don't go in for strange fruit and vegetable combinations in purée because it just isn't similar to what we eat as adults. I wanted to give my daughter a taste for foods that would lead her on to eating similar foods to myself and my husband so that I could cook for us all together as soon as possible, rather than cooking lots of different meals! Right from the start of weaning, I have fed my daughter savoury meals, usually followed with some fruit. Initially this was a savoury vegetable purée followed by a fruit purée. My last tip in weaning is that once your little one starts to take in a little purée and is getting used to the tastes, I would make sure that you are giving him or her something starchy to fill them up. For example sweet potato, butternut squash, swede etc. and if you are giving them a purée that doesn't have anything starchy then mix in a little potato.