Hello. A child's party can be a large affair involving the whole class or a smaller one with just a few friends.
Children tend to have large parties in their first few years at school and these scale down as they get older and their friendship circles get smaller.
First off, pick a date, usually a saturday or sunday nearest to the childs big day. It may be worth asking her teacher if another child has a birthday close to your DD's. You could have a joint pary with them or if you want your own then you can make sure that they do not happen at the same time (very awkward!) You may need to be flexible with the date depending on your venue or entertainment choice.
There are lots of options, softplay parties are popular. Also hiring a hall and a having a disco or entertainer. I would choose a venue first and make sure it is free. Church halls are usually the best bet, quite resonable to hire.
Next, decide what sort of entertainment. If you google or yell.com children's entertainers in your area, there will be loads. I always phone and enquire about cost, type of entertainment provided, numbers of children etc. Phone a few and ask around, personal recommendation is always best. People at school will have used them and will pass on telephone numbers.
When you have booked your venue and entertainer, you can concentrate on invitations and food. Most schools will let invitations go in in bookbags to be distributed by the class teacher, although some have rules about this, worth a check.
Most mums stay around at parties while children are in reception and year one. They usually, hang around on chairs at the side of the hall and chat. Some hosts provide tea or soft drinks for them but it is not usually expected.
Food for children is mostly of the sanwiches, crisps and chocolate fingers variety.
You can choose a venue, for example softplay, where all you do is turn up and they provide food etc.
Hope this helps, you may want to think about, party bags, pass the parcel, decorations for the hall and a cake.
Good Luck