If you are not ready to date, then dont do it. As it will come across to the other person, in one way or another. Firstly you need to love yourself and embrace what you have to offer before expecting someone else to do it. This in itself is the first step yet the hardest one to take.
If you seriously have any doubts or concerns, then don't do it, but if you do .. then have heaps of fun ! I am learning that the physical aspect to one person is not who they are, it is only one part of it the package.... one that can be easily fixed. So go and enjoy ... get out there and have fun, don't let your weight hold you back